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What Can Cause Heavy or Stiff Steering?

I was driving my car the other day and out of nowhere, my steering wheel became stiff. It was really hard to turn the steering wheel. It felt like I was wrestling with an alligator. When this kind of thing happens to you for the first time, you immediately suspect a flat tire. So, I pulled over and check all of my tires which were fine. Then, I got back into the car and started to turn the wheel left and right, and I could really hear some grinding and whining noises while I struggled to turn it.

Now, if this has happened to you and you want to know what can cause heavy or stiff steering, read on as I go into the most common reasons. This type of issue doesn’t occur very often, but it can happen to anyone. Right after it happened to me, I wanted to educate myself as much as possible before getting ripped by some mechanic. Here is what can cause heavy or stiff steering:

1. Incorrect tire pressure

What Can Cause Heavy or Stiff Steering?

Incorrect tire pressure can cause heavy or stiff steering. This might seem like an obvious one, trust me, tire pressure is the most commonly overlooked issue. So, starting out with issue number one is incorrect tire pressure. Low tire pressure causes excessive resistance due to higher friction not allowing the steering to move freely. Typically, recommended tire pressure is between30 to 35 PSI. A good generic value is 32 PSI. However, this can vary between vehicles and tire types. The tire pressure specific to your vehicle can be found in your owner’s manual, or on the information tag on your door jamb.

2. Vehicle has been sitting for too long

What Can Cause Heavy or Stiff Steering?

A vehicle that has been sitting for too long can definitely have issues with the steering. If your vehicle has been sitting for an extended period of time, your steering components can become somewhat seized. That can be either from rust or, the lubrication has dried out. This can include anything from the steering column assembly, all the way down to your ball joints or tie rods.

You can apply lubricating oil on some of the bushings which are found on the steering column. You can also apply lubricating oil on splines and small universal joints. However, some of the universal joints may have seals to keep out dirt and this will prevent any oil from getting into the joint. Others may have grease fittings such as ball joints or tie rods. This means that they are serviceable components.

Always use a ball joint compatible grease when greasing these components and do not apply more than three pumps of grease. Pump the grease gun slowly and watch the boot slightly move. Then, stop and move on to the next joint. Too much grease can break the seals on these boots allowing the grease to escape and having foreign contaminants enter the joint causing a premature failure.

If you have no serviceable components, the stiffness may eventually disappear after some usage. You can use a grease needle on non-serviceable joints, but it’s not something I typically recommend. This can cause a premature failure because once that boot has a puncture from the needle, it can grow due to the rubber deterioration. This will allow grease to escape and dirt to enter.

3. Worn out belt that drives the power steering pump

What Can Cause Heavy or Stiff Steering?

A worn-out belt that drives the power steering pump can cause stiff or heavy steering. If you hear a squeaking noise after you turn the steering wheel, the issue could be the belt that is driving the power steering pump. In most cases, the belt is loose. A loose belt can be caused by it being worn and stretched which will require replacing.

Replacing the belt with a new one is probably the best option. The belt simply needs to be adjusted manually if your vehicle does have an adjustment. While you are at it, you may have a worn tensioner that is not maintaining sufficient pressure on the belt.

4. Low or contaminated power steering fluid

Low or contaminated power steering fluids can cause heavy or stiff steering. If your vehicle is equipped with power steering, your power steering fluid may be low or a replacement is required. When there is a fluid-related issue, this typically results in a whining power steering pump. But, with that being said, the pump can also be failing too.

The pump may whine when the vehicle is idling and usually worsens when operating the steering. Fluid level checking procedures can vary between vehicles. There are also maintenance intervals for fluid replacements as well. This information should be outlined in your vehicle’s owner’s manual. If your vehicle is equipped with a filter for the power steering fluid, it’s best if you change that as well.

5. Improper wheel alignment

Improper alignment can also cause stiff steering. I have an article that explains alignment in depth. But, here is a quick overview. The toe angle and caster angle can affect your steering operation. Different angles can cause the steering to fight against each other, or excessive positive cast or angle, while it improves straight line stability, will create harder steering operation.

6. Failing steering components

Failing components in the steering system can cause heavy or stiff steering. This could be something less costly to replace, such as a ball joint or tie road. As I mentioned before, these components have a rubber booth which is intended to keep lubrication in and dirt out of the joint. Of course, with time, these boots will eventually become worn out and will allow foreign contaminants to enter and thus prevent the steering from operating smoothly.

Depending on what your vehicle is equipped with, a more costly issue you can have is a failing power steering pump, failing steering rack, or steering box. A failing steering pump makes a whining sound which is pretty easy to distinguish. However, a steering rack or box can sometimes be a little harder to diagnose. You may notice excessive play when operating the steering. Perhaps even a grinding noise when turning.

How to Test a Car Battery [Easy Guide]

Car batteries will last anywhere from three to five years, sometimes even longer. The lifespan of the battery depends on the use, climate, and quality of the battery itself. Having a bad battery can cause a series of problems and to stay on top of that, I suggest checking your car battery once it reaches 3 years of age.

Also, I had an electrical issue with my vehicle not too long ago. I went to the mechanic shop and they suggested that I get a new car battery even though my battery was just 14 months old. So, I was a bit skeptical, to be honest. That’s why I went straight home and tested my car battery. It turned out that my battery was working fine and that something else was the problem.

So, before you take your car to the mechanic shop and replace your battery, let me show you how to test your car battery. Let’s dive into the details and by the end of this article, you will know how to test a car battery.

How To Test a Car Battery

A worn or faulty battery will cause no starts, engine turning over slow especially in the cooler weather, battery discharging quickly, electrical malfunctions in your vehicle, and possibly a warning light on your dashboard.

That’s why I have put up this easy guide on how to test a car battery using simple and affordable tools. By the end of this article, you will know how to test a car battery.

1. Required tools for testing a car battery

How to Test a Car Battery

In order to test a car battery, you will need some equipment. Keep in mind that the battery testing equipment is affordable and can last you for a long time. You will need:

  1. Digital multimeter. The digital multimeter for car batteries that I got is less than $20 and you can order it on
  2. Digital battery analyzer. You will need a digital battery analyzer to test the CCA which stands for Cold Crank Performance(amps). I got my battery analyzer for around $30 on

2. Locate and remove the car battery

How to Test a Car Battery

Once you have your battery testing equipment in order, the next is to locate the car battery. In most vehicles, the battery is located under the hood. However, on some vehicles, the car battery can be located in the trunk or under the rear seat. I prefer removing the battery before testing it because it gives me more access and I don’t have to worry about the terminals touching.

Disconnect the battery terminals using the appropriate tools. Always start with the negative terminal first to reduce the chance of a short when using your tools. Once the negative clamp has been removed, then move on to the positive. Then, remove the hold-down clamp. Take out the car battery while holding it leveled so you don’t spill out any acid from the vent holes.

IMPORTANT: When charging or testing your car battery, always do this in a well-ventilated area so there’s no risk of fumes building up which could risk an explosion.

3. Test the voltage using a multimeter

How to Test a Car Battery

Before testing the battery, you will need to ensure that the terminals are clean. Set the multimeter to the two-digit DC voltage setting. Then, touch the appropriate probes on the negative and positive terminals. The black goes to the negative and the red to the positive terminal.

A properly working 12V car battery should have a reading between 12.7V and 11.9V. Anything below 11.7V to 11.58V is considered moderate, and under 11.31V is considered bad. If you have a reading below 11.31V don’t even bother recharging it. Go ahead and replace it with a new battery. You can check out some car batteries on

4. Test the cold-cranking performance

How to Test a Car Battery

Testing the CCA or the cold-cranking amps can be done with a battery analyzer tool. The car battery and CCA will be different for vehicles because it depends on the engine size. Larger engines need more power, therefore, higher voltage batteries.

On this particular battery that I am performing a test, the CCA is 410 on a temperature -18 degrees Celsius or 0 degrees Fahrenheit. Connect the red positive clamp onto the positive terminal of the battery and the black clamp onto the negative terminal of the battery. Turn on the battery analyzer tool and select the type of battery and the CCA written on the battery.

If you get a reading lower than what is written on the CCA label, then you will need to replace your car battery. I’ve tried recharging my old battery but simply it was just a waste of time and energy. Once your car battery goes bad, it’s time for a new one.

5. Install a new battery or reinstall the old one

Once all the testing is done, you will know if your battery is up for a replacement or not. Like I said before, if you have a bad car battery, replace it. It is not worth the headache. It can leave you on the side of the road and towing costs much more than a new car battery.

Whatever you decide to do, place the battery in the same position as before and tighten the hold-down screw first. Be careful not to touch the clamps. Attach the positive terminal first and then the negative.

How to Find and Fix a Leaking Tire Valve

A leaking tire valve is a very commonly overlooked area in a leaking tire. The Schrader tire valve can form a leak with age, either from dirt or having a damaged seal. Sometimes, the tire valve can even be faulty from new. I have had this issue in the past and I have successfully replaced my tire valve with a new one.

So, if your tire is leaking air and you suspect that it is the tire valve, or you don’t know what is causing your tire to leak air, read along. I will be showing you how to find and fix a leaking tire valve.

Tire Valve Assembly

1. The valve casing

How to Find and Fix a Leaking Tire Valve

The Schrader valve casing can be rubber or solid but the valve inside is the same. The only difference with a valve is the temperature rating which would be used in a commercial application such as something with a heavy load and extensive driving.

On the image above I have the most common form found on vehicles. The casing is installed from the inside when the bead of the tire is broken or the tire has been removed and is pulled outwards. The groove on the bottom is what clips into place either on the aluminum or steel wheels.

2. The tire valve

How to Find and Fix a Leaking Tire Valve

The red ring on the outside is the outer seal that goes against the casing. The threaded portion moves towards the top. The center spring-loaded portion is the valve. When the air chuck is put into place, it’ll push on the center portion allowing air.

On the bottom of the center portion that faces the inside of the tire, there is another seal on this surface too. As for the outer casing, this is just a shell to hold the valve. It’s hollow in the center and there is a threaded portion on the inner-outer side for the valve.

How to Find and Fix a Leaking Tire Valve

1. Gather the needed materials

How to Find and Fix a Leaking Tire Valve
  • Schrader valve tool. For removing the tire valve, you will need a valve removal tool. I have used this remover tool that I bought from and i’m extremely impressed with its versatility.
  • Tire valve stem. If the tests show that your tire valve is leaking air, you will have to replace it. I usually order the valve stem from
  • Soapy water. We will be using simple soapy water to test the tire valve for leaks before we replace it.

2. Remove the valve cap

Removing the valve cap is the first step. Valve caps are important as it protects the valve and keeps any dirt out which may shorten its life or cause any issues. Some wheels have a metal cap, however, plastic caps are the most common. Be careful with metal-style caps. I’ve had issues in the past where they’ll corrode and seize onto the valve stem.

3. Apply soapy water to the valve

How to Find and Fix a Leaking Tire Valve

The tire pressure must be present. Meaning, even if your tire is leaking air, you have to inflate the tire. Then, using a spray bottle or a bottle with a soap and water mixture pour it on top of the valve. This mixture can be dish soap, hand soap, or car wash soap. Basically, something which allows for bubbling.

If the valve is leaking, you’ll automatically see bubbling as shown in the image above. Sometimes only tightening the valve is required as it might get loose over time. But if that doesn’t fix the problem, continue with the following steps.

4. Remove the faulty valve stem

If simply tightening the valve stem didn’t work, it’s time to replace it. Align the tool bit and you’ll feel it clip into place. Then, turn counterclockwise to remove it. Once removed, pull out the valve stem with your fingers, or if air pressure is still present in the tire it will push it out on its own.

5. Install the new valve stem

You can purchase replacements on their own, or just get a new valve stem and swap over the internal component. What I usually do if I am taking a wheel in to get a tire replaced. The shop will install new valve stems as the rubber can dry out and crack with age, so I remove the valve and keep it as a spare.

Take the new valve and drop it into the casing. Be mindful not to over-tighten it because it is really not needed. You may just cause damage to the new valve stem.

6. Inflate the tire to the correct PSI and check for leaks

You are near the end of the tire valve replacement job. Now, all you have to do is inflate the tire to the manufacturer-recommended PSI. That information will be written on the tire.

After you’ve done that, it is time to check the valve with soapy water to confirm that you have no leaks. I would also recommend rinsing off the soap and water mixture just with water to ensure you don’t leave any staining on your wheels.

Before reinstalling the cap, give the valve a flick to remove any water and then install the cap. Some valve stem removal tools have a pointed portion that is used to clean the stem from debris. Any debris inside may cause issues where the tire won’t pump up properly.

How to Find a Leak in your AC System using a UV Dye

Over time with age, the components or seals will fail eventually causing a leak for the refrigerant to escape from your car AC‘s system. When the system is low on refrigerant, it’ll either work poorly. If the refrigerant leaks out enough your AC won’t work at all.

It doesn’t matter if it’s winter and you are not using your AC. You must have an operating vehicle at all times. Something as a small refrigerant leak can grow up into a much bigger issue if left untreated. So, in this article, I will show you how to find a leak in your AC system using a UV dye.

How to Find a Leak in your AC System using a UV Dye

If your AC system is leaking, it is only a matter of question when you will run out of refrigerant. At that point, your AC will either work poorly or not work at all. So, if you have noticed that your AC is not working properly even though you added refrigerant recently, it is possible that your AC system is leaking somewhere.

But where exactly? The first step is adding a dye to the system which will help you pinpoint the leak. Follow the steps and you will learn how to find a leak in your AC system using a UV dye.

1. Materials needed for this procedure

Before you start with the procedure of finding a leak in your AC system, there are some items that you will need.

  1. UV dye for AC systems (see prices on
  2. UV enhancing safety glasses (see prices on
  3. A UV light (see prices on

2. Locate the low-pressure port

How to Find a Leak in your AC System using a UV Dye

The AC system is filled through the low-pressure port side on the AC system which is found under the hood. It’s a smaller port covered with a cap that may be labeled with an L (meaning low-pressure side). The low-pressure port might not be in the same location in all vehicles, but it looks the same on all models.

3. Connect the refill tool to the low-pressure port

Once you remove the cap, you will find a Schrader valve. You’ll need a special tool to fill up the AC system. For this procedure, I’m using a refill tool that I got from Typically, these are found with a recharge kit, a quick disconnect that only fits onto the low-pressure side, and a gauge to monitor the pressure in the AC system.

It is important to shake the can first before using it. The valve has a punch that is operated by the handle. You need to make sure that it’s fully retracted before screwing on the can. Then, screw on the can.

4. Start the engine and turn the AC on

How to Find a Leak in your AC System using a UV Dye

Start the engine and let it run. Make sure that you have enough fuel to last you at least 30 minutes. Then, turn on the AC. Set up the fan to highest and the temperature to coldest. The AC compressor may not turn on if it’s excessively low. However, if the rest of the system is in proper working order, once you have enough pressure, the pump will cycle the dye through the AC system.

5. Add the dye into the AC system

Safety glasses are highly recommended as refrigerant can cause damage to your eyes. Attach the recharge tool for the low-pressure side of the AC system. Turn the valve in to pierce the can. Then, slowly open the valve and monitor the pressure. This may take a few minutes and shaking the can does help a little with refilling the system.

Constantly monitor the gauge and keep the pressure in the blue area. This is the safe zone. However, depending on your recharge tool, the colors may vary on what is an acceptable pressure range and what isn’t. You don’t have to use the full can, but enough where the pump can recirculate the dye through the AC system.

6. Remove the refill tool and check for leaks

Once you finish with the refilling process, close up the valve and then remove the recharge tool. You’ll want to use a wax and grease remover on a q-tip to clean inside the charge port to remove any dye so we don’t have a false result. Finally, reinstall the cap. Depending on how bad the leak is, you may need to run the system anywhere from an hour to a few days and check back.

For finding the actual leak you’ll need yellow safety glasses as you’ll be unable to see the dye without them and a UV light. The best time to check for leaks is at night. Make sure there are no other lights around. Turn on the UV light and inspect all areas of the engine bay where the AC lines are located such as the compressor, condenser dryer, and even the evaporator.

The condenser might be hard to check and removing the grill may make the inspection much easier. This is a common component for developing a leak from a stone impact. You’ll be looking for a fluorescent area where the dye has leaked out. If you are unable to locate the leak, then, you might have to check the low-pressure cap as it can be the cause of the refrigerant leak.

How Fuel Tanks and Fuel System Works

The fuel system is fascinating, to say the least. It is a system that contains a lot of parts that all work synchronized in order to deliver fuel to the engine continuously. I always wanted to learn more about fuel systems and how they work. So, I did some research online and talked to couple a of mechanics, and here is what I’ve learned.

Safety Information

Before working on any part of the vehicle, you must follow these three simple rules:

  1. No smoking. Never smoke when working on the fuel system keep open flames and sparks away from your workstation.
  2. Safety first. Always wear safety glasses when working on or around any vehicle.
  3. Relieve the fuel system pressure. You need to relieve the fuel system pressure before you hook up a pressure gauge. There are 5 methods of relieving fuel system pressure.

Types of Fuel Systems

There are two types of fuel systems used in most vehicles. They are very similar, however, they deliver fuel in slightly different ways.

1. The return-type of fuel system

The return type fuel system components are:

  1. Fuel tank
  2. A fuel pump
  3. Fuel lines
  4. A fuel filter
  5. Fuel rail with injectors
  6. Pressure regulator
  7. Return line

On a return-type fuel system, the pressure regulator is located on the fuel rail. Once upon a time, gravity moved the fuel from a vehicle’s tank to the carburetor. Today’s program fuel injection system needs to have a pressurized and constant supply of fuel delivered to the injectors at all times. The supply of this constant pressurized fuel is enabled by the fuel pump.

2. The returnless type of fuel system

The returnless type of fuel system has the following components:

  1. A fuel tank
  2. Fuel pump
  3. A fuel filter
  4. Pressure regulator
  5. Fuel lines
  6. Fuel rail with injectors

On a returnless fuel system, the pressure regulator is located inside the fuel tank.

Fuel System Components and How They Operate

1. Fuel Pump

How Fuel Tanks and Fuel System Works

The fuel pump has a function to pressurize the fuel system for engine starting and then continue providing fuel for the injectors while the engine is running. When you turn on the ignition switch, the ECM PCM activates the pump relay for 2 seconds to turn the pump on and pressurize the system.

If the ECM PCM does not register the engine as running, it will turn off the relay, thus stopping the fuel pump. If the ECM PCM does see the engine running, it will keep the fuel pump running continuously. Some cars are equipped with multi-speed fuel pumps. These fuel pumps offer more precise control of the fuel supply. In the older type, the ECM PCM varies pump speed by applying either low or high voltage to the pump depending on engine fuel requirements.

When less fuel is needed, the ECM PCM deactivates the fuel pump relay and the current goes through the fuel pump resistor to lower the output of the pump. When fuel demands increase, the ECM PCM activates the fuel pump relay so that current can bypass the resistor and go directly to the pump to increase output.

Late-model cars are equipped with a separate fuel pump control unit (FPCU) that has a function to change the speed of the fuel pump according to the driving conditions. The fuel pump has three operational speeds: low, mid, and high. When engine speed and load are low, the fuel pump receives 9 volts. Then, as engine speed and load increase, the voltage will increase to 10 volts.

The pump assembly consists of a:

  1. Strainer pump
  2. Motor pump
  3. Impeller relief valve
  4. One-way check valve

The pump is submerged in the fuel and driven electrically to turn an impeller which will draw fuel through the strainer and develop pressure. The fuel then exits via a one-way check valve. The purpose of the check valve is to prevent pressure in the fuel rail from flowing back into the tank when the fuel pump is off. That way, the fuel system will have sufficient pressure when the vehicle is started. The pressure relief valve will open and discharge fuel back into the tank should pressure become excessive.

2. Fuel Pressure Regulator

The purpose of the regulator is to keep the fuel at a constant and specific pressure. There are slight differences between the return type regulator and the returnless type regulator. The regulator consists of a housing valve, a diaphragm, and a spring. The spring holds the valve closed and allows the fuel pressure to build up against the diaphragm.

When the fuel pressure overcomes the spring pressure, the valve opens and allows excess fuel to bleed off and return to the fuel tank. The regulator on a return-type fuel system is located near the end of the fuel rail. When the regulator is connected to the intake manifold, a vacuum is routed to the pressure regulator to help overcome the spring force. This is done to maintain constant pressure. The difference between fuel pressure and manifold air pressure.

When the throttle is closed, the manifold vacuum is high and the manifold pressure is low. This results in lower fuel pressure. As the throttle opens, the manifold vacuum decreases while manifold pressure increases. This results in higher fuel pressure.

Regulators that are connected to the intake air duct are not controlled by an engine vacuum. The hose is there to provide unrestricted movement of the regulator diaphragm. These types of regulators operate like returnless regulators where the ECM PCM compensates for changes in intake manifold pressure.

On a returnless type system, the regulator is located in the fuel tank and is part of the fuel tank unit. In order to keep the fuel cooler and to reduce evaporative emissions, the manufacturer placed no return line between the fuel rail and fuel tank.

3. Fuel Pressure Damper

Some vehicles have a fuel pulsation damper located on the fuel rail. The fuel pressure damper is used to absorb pressure pulses and to reduce noise caused by the injectors opening and closing rapidly. The damper consists of a diaphragm and calibrated spring. The injectors are opening and closing and create a pressure shock wave which is absorbed by the diaphragm as it compresses the spring.

4. Fuel Injectors

The injector sprays atomized fuel into the intake port of the cylinder. This action is operated electrically. They are normally closed. The ECM/PCM fully opens the injector for a precise time measured in milliseconds in order to deliver the correct amount of fuel to mix with the incoming air. The longer the fuel injector is in the open position, the bigger amount of fuel is sprayed into the combustion chamber. The fuel injector body is sealed between the intake manifold and the fuel rail.

The internal components of a fuel injector include:

  1. An inlet screen
  2. Electrical connector
  3. Electromagnetic solenoid coil
  4. Plunger
  5. A discharge nozzle

The injector discharge nozzle is designed to optimize fuel atomization by creating extremely fine droplets. The improved atomization provides stronger engine performance and reduces emissions.

Troubleshooting The Fuel System

Troubleshooting The Fuel System

The fuel has to have a constant fuel pressure so the ECM PCM can control the air-fuel ratio accurately. Low fuel pressure can be caused by low or no pump output, a restricted strainer, a restricted filter, a restricted supply line, or a stuck open or weak spring in the regulator.

To isolate which component is responsible for the low-pressure, you can always check for any service bulletins or service news articles that apply and follow the procedures they provide. If there are no bulletins or service news articles, start with the easiest component to test.

1. Inspect the fuel lines

Start by inspecting the fuel lines between the fuel tank and the fuel rail for any leakage, broken pipes, and other damages.

2. Check the pressure regulator

On a return-type fuel system, the pressure regulator would be the next place to start. To determine if the pressure regulator is stuck open relieving too much pressure, pinch close the return line with swivel jaw hose pinching pliers. If the pressure rises, the regulator is likely at fault.

3. Replace the fuel filter and strainer suction filter

If the pressure regulator is okay, the fuel filter and strainer suction filter should be replaced. Before you replace them, you need to make sure that whatever condition caused them to become clogged is no longer present. Otherwise, they may become clogged again soon. If you are working on a returnless fuel system, replace the pressure regulator and fuel filter.

4. Check the fuel pressure

If your vehicle has a long crank time or hard starting, observe the pressure reading right after shutting off the engine. There should not be a rapid fuel pressure drop immediately after shut off. If the pressure drops fast, the internal possibilities are: check valve in the fuel pump not seating, leaking injectors, pressure regulator not closing, or an external leak such as fuel hoses and lines.

5. Test the injectors

Remove the fuel rail and injectors together and check for leaking by turning the ignition switch on. You can also check for leaky injectors by pinching off both the fuel inlet and return lines and then monitoring fuel pressure.

6. Inspect the fuel pump check valve

If the injectors are ok, then the fuel pump check valve is the issue and the pump will need to be replaced. Note that the check valve is an integral part of the fuel pump and cannot be separately replaced.

7. Look for restrictions in the return line after the regulator

High fuel pressure can be a result of a faulty regulator or a restriction in the return line after the regulator. Check the vacuum hose to the regulator first. If it is disconnected or blocked from the manifold vacuum, the pressure will be high. If you see fuel in the vacuum line, the pressure regulator diaphragm is leaking and needs to be replaced.

Fuel Delivery System Operation

Like other electrical components on the vehicle, the fuel pump and injectors require power to operate. But, they don’t just operate all the time. Instead, they are controlled by the ECM PCM through relays to operate at the correct time.

A relay is an electromagnetic switch that has two sides: power and control. The ECM PCM operates the control side of the relay to provide a power path to the fuel injectors and the fuel pump. Fuel injectors are on/off solenoid valves that spray fuel into the intake port of the cylinder. The fuel injectors require power and ground to operate.

The power to the injectors comes through the PGM-FI main relay which is energized whenever the ignition switch is turned on. The ECM PCM provides the injectors with a ground path. This is also how it turns the injectors on and off. When there is no ground, the injector is closed and is not spraying fuel. When there is ground, the injector is open and is spraying fuel. The longer the ground is on the longer the injector is open and the more fuel that enters the combustion chamber.

The ECM PCM uses various inputs to calculate exactly when grounding injector opening time should begin and how long it should last. The opening time is called ”injector duration” and is measured in milliseconds-thousandths of a second.

A vehicle decelerates with a closed throttle. The ECM PCM turns the fuel injectors off to save fuel and it turns the injectors back on right before the engine reaches idle speed. This function is called ”fuel cut” and is normal. Fuel cut-off also occurs when engine speed gets too high regardless of the throttle position. It does this to protect the engine from over-revving.

How Fuel Tanks and Fuel Systems Work

The heart of your vehicle’s fuel injection system is the electric pump located inside the gas tank. The pump delivers a constant volume of fuel to the engine at high pressure so that adequate supply is available to the injectors at all times. Depending on the vehicle the fuel pump may be serviced separately or be part of modular fuel sender assembly. Be aware that modular assembly is more expensive since it incorporates several components into a single unit.

The fuel pump strainer is your vehicle’s first line of defense against fuel system contamination. Often referred to as a fuel sock because of its appearance. The strainer is located inside the gas tank, just below the pump. In addition to filtering contaminants, the strainer also provides a wicking action that draws fuel into the pump in the same way that liquids are drawn into an absorbent paper towel. Although the strainer is not a maintenance item, it should always be replaced if you’re installing a new fuel pump.

The electric pump used in a fuel injection system is capable of delivering fuel at pressures that exceed engine requirements. Because of this, a regulator is used to adjust fuel delivery pressure according to engine load. A faulty regulator causes fuel pressure to be incorrect resulting in a variety of engine performance problems such as stalling, hesitation, and lack of power.

The regulator is mounted on the fuel rail which may not be readily accessible as it is on this engine. Consequently, replacement costs will vary. The efficiency of today’s engines is due in large part to the fuel injector controlled by the vehicle’s onboard computer. The injector sprays fuel into the cylinders in precise amounts.

Most engines today are equipped with multipoint fuel injection which uses one injector for each cylinder. The injectors are mounted on a rail located on the intake manifold. Faulty injectors can cause a variety of symptoms ranging from hard starting to hesitation. Be aware that on some engines the injectors can be difficult to access which will increase the cost of replacement significantly.

As the name implies, an oxygen sensor detects the amount of oxygen present in the exhaust gases and then relays that information to an onboard computer. The oxygen sensor enables the computer to make continuous adjustments to the air-fuel mixture resulting in maximum engine performance with minimal emissions.

Oxygen sensors are also used to evaluate the efficiency of the catalytic converter based on the converter’s ability to store and release oxygen. Unlike other engine sensors, the oxygen sensor is a maintenance item. It needs to be checked periodically and replaced according to the manufacturer’s recommended interval.

What Are The 9 Symptoms of a Faulty EGR Valve?

The EGR valve is known for collecting grime due to recirculating the exhaust gases. This means that at some point in time, your EGR valve might become faulty. It’s best if you know the symptoms of a faulty EGR valve and act accordingly. Sometimes, simply cleaning the EGR valve without removing it will do the job, sometimes it won’t.

The purpose of the EGR is to open up and recirculate part of the exhaust gases back into the intake manifold. These exhaust gases help reduce the temperature of combustion. This is super important because nitrogen oxide is formed at high temperatures. So, by reducing the temperature it reduces nitrogen oxide formation.

When it comes to symptoms of a bad EGR valve, it can go in two different directions: Symptoms of a stuck open EGR valve or you can have symptoms of a stuck closed EGR valve. I will now go in-depth and show you what are the 9 symptoms of a faulty EGR valve.

What Are The 9 Symptoms of a Faulty EGR Valve?

What Are The 9 Symptoms of a Faulty EGR Valve

A faulty EGR valve is something that happens more often than we want. It is a hardworking part of the vehicle that is exposed to a lot of exhaust gases throughout its lifespan. This means that carbon buildup is inevitable. That’s why I have done in-depth research and provided you with what are the 9 symptoms of a faulty EGR valve:

1. Check engine light

What Are The 9 Symptoms of a Faulty EGR Valve

The easiest way to figure out if your EGR valve is faulty is by noticing your check engine light on. There are some codes related to a bad EGR valve: P0400, P0401, P0402, P0403, P0404, P0405, P0406, P0407, P0408, P0409. You can read these codes with an OBD Scanner (see prices on or by going to the parts store near you and they’ll most likely do it for free.

2. Failed emissions test

If your car fails the emissions test, you most likely have a faulty EGR valve. This can be due to a stuck closed EGR valve. A stuck closed EGR will prevent the exhaust gases from coming into combustion. If the exhaust gases don’t come in, the temperature inside the chamber will increase and produce more nitrogen oxide. Therefore, too much nitrogen oxide will fail your emissions test.

3. Engine knock

The third symptom you might be experiencing if your EGR valve has failed is engine knocking. Engine knocking is when an unplanned mini detonation occurs during the power stroke in combustion. People describe it as a pinging noise.

A stuck closed EGR prevents exhaust gases from coming inside of the combustion to cool it down for proper temperature levels. Hot temperature levels inside the combustion can ignite the air/fuel in unwanted times which creates your engine knocking.

4. Lack of acceleration

Lack of acceleration can be a clear sign that your EGR valve is faulty. A stuck open EGR valve can be the cause of this. A stuck open EGR will continuously and exhaust gases back into the combustion chamber. These gases will take up space, therefore limiting the amount of air that needs to enter in order to achieve optimal engine performance. That is why your acceleration is lacking.

While accelerating, the engine needs more fresh air to get its peak performance. More exhaust gas instead of fresh air will also alter the fuel injection rates which will further decrease the performance reasonably. You can and should try to clean your EGR valve without removing it. I have another article that explains in great detail how to do that. Check it out here.

5. Rough idle

Another symptom of a faulty EGR valve is a rough idle. The reason for this is because the EGR is stuck open. It takes up space from the exhaust gases inside the combustion, therefore not leaving much room for air to combust efficiently with fuel. This leads to improper combustion which results in your car having vibrations and rough idle.

6. Fuel smell around the car

If the EGR is not functioning properly, the fuel inside cannot burn efficiently due to disturbed air-to-fuel ratios. This will emit more unburnt fuel into the exhaust thus making a pungent fuel loader. This symptom occurs mostly when the car is first started or when the engine is cold.

7. Bad fuel economy

A faulty EGR alters the combustion efficiency of the engine badly. You might even find yourself in a situation where you need to press more on the gas pedal than usual to go forward. This can make the overall efficiency of the engine go down and affects the gas mileage badly.

See more: Why Is My Car Wasting So Much Gas [9 Reasons]

8. Black smoke from the tailpipe

If your EGR valve is faulty, you might notice gray, dark, or black smoke coming out from the tailpipe. The reason for this is because when your EGR valve is faulty, it restricts the airflow to the engine. At this point, your engine is running rich which means it is burning more fuel than air.

The reason for this can be either a faulty EGR valve or just a clogged EGR valve. Before you replace your EGR valve, you should always try to clean the EGR without removing it.

9. Engine misfire

If your EGR valve is faulty, it can cause an engine misfire. There are two ways to diagnose this issue. The first one is to scan your vehicle with an OBD scanner and look for a P0300 – random misfire error code. The second one is to physically check the EGR valve and see if the gasket is broken or cracked. A simple crack can cause a vacuum leak.

The carbon deposits that accumulate up in the valve will cause the valve to stay off of the seat and that will give the random misfire at an idle and create a drivability concern. If you check the EGR physically and notice some cracks, replacement is in order.

I really hope you liked our article. My 2007 Hyundai had this issue and to be honest, I just didn’t care to diagnose it myself. That’s why I paid some mechanic to replace an EGR valve that could have been fixed with a simple cleaning. Always do some research before you throw your hard-earned money. Share your thoughts and experiences in the comment section.