Signs of bad idle control valve

The number one cause for high idle is an imbalance in air pressure. An engine that is idling too high may be caused by a faulty idle air control motor valve that has completely fai...

Signs of bad idle control valve. Vacuum leaks that let air into the manifold can also cause a high idle speed. A defective idle speed control valve that is stuck in the extended or high idle speed position can also be the cause. 11. Lean Engine Condition. Another usual sign of an unclean or malfunctioning car carburetor is when the vehicle runs low.

The most common symptom of a bad VVT solenoid or oil control valve is a check engine light on your dashboard. You may also notice issues with the performance, like rough idle, rough acceleration, increased fuel consumption, or low engine power. Here is a more detailed list of the signs of a bad or failing oil control valve to look out for: 1.

Signs Of A Failing Idle Control Valve . Several signs could indicate a bad idle control valve. But, these symptoms may also show up due to other engine troubles. In that case, it’s best to have a mechanic inspect your IAC valve to ascertain if that’s what is causing these symptoms. Here are some signs that could give you a heads up about a ...VVT solenoid replacement will involve possibly a diagnostic fee, then labor and the cost of the parts as follows: If your mechanic charges a diagnostic fee, it could range from $65 to $100. Average parts cost will likely be somewhere between $50 and $250. Labor for the VVT replacement could range from $75 to $200.The idle air control valve (IACV) is a device attached to the throttle body that helps keep the engine of a vehicle running without throttle input, such as when the car is idling in traffic or parked with the engine running. It regulates the amount of air entering the engine, which helps control the engine's RPM according to the driver's ...A PCV valve is a necessary part of an engine that allows the pressure that builds in the crankcase to be released. When a PCV valve fails, and the pressure is not released, it can cause several symptoms, such as blowing out gaskets or engine misfires. The symptoms will vary and depend on whether the valve is stuck open or closed.Blood flows out of your heart and into a large blood vessel called the aorta. The aortic valve separates the heart and aorta. The aortic valve opens so blood can flow out. It then ...The emission of blue smoke from the exhaust system is one of the most common signs of a bad valve seal. You may also notice a burning oil smell. A bad valve seal may also produce some other symptoms such as misfiring, oil accumulation on the spark plug tip, rough idle, reduced engine power, external oil leaks, or poor acceleration. The most ...

Modern autos’ two most frequent problems which can result in bad idle air control valve symptoms include: 1. Blockage In the Idle Air Control Valve. Contaminants, dirt, and debris can enter the valve chamber during this exchange due to the volume of air going in and out of the idle air control valve.Jan 24, 2019 · By having a fully functional idle speed control valve, the engine idle speed never goes below 900 RPM or above 1,100 RPM. 5 Bad Symptoms. If you have an idle speed control valve which is starting to go bad, then you need to replace it as soon as possible. Summary. An intake manifold runner control (IMRC) valve is part of the system that opens and closes the flaps inside variable intake manifolds. An illuminated check engine light, engine performance issues, and reduced fuel economy are some common symptoms of a faulty IMRC valve.A sudden change in the pressure (i.e., pressure spikes in the fuel system) may lead to the failure of the purge valve’s parts. 2) Bad Solenoid. The purge valve is also known as a purge solenoid. It works on the solenoid mechanism that controls the valve’s closing and opening. When the solenoid goes bad, the valve’s operation will be ...What are the Symptoms of a Bad Idle Air Control Valve. This morning my Idle Speed was all over the place. Thanx Reply Like. 03-16-2011, 01:49 PM #2 Kubs. Le Mans Master . Member Since: Oct 2007. Location: Akron Ohio. Posts: 8,880 Likes: 3,100 Received 1,781 Likes on 951 Posts 2023 C5 of the Year Finalist - Modified ...A bad idle control valve can cause a multitude of issues with your car. Check out the Drive’s Garage Guide to identify the signs of a bad idle air control valve. Your idle...The most common thing you’ll notice from a bad vapor canister purge valve is that you’ll get a check engine light that you weren’t expecting. While the symptoms can change depending on whether or not the valve is stuck open or closed, one thing that shouldn’t change is that you should get a check engine light. 2.Feb 20, 2023 · The most common symptom of a bad VVT solenoid or oil control valve is a check engine light on your dashboard. You may also notice issues with the performance, like rough idle, rough acceleration, increased fuel consumption, or low engine power. Here is a more detailed list of the signs of a bad or failing oil control valve to look out for: 1.

The most common symptoms of a bad exhaust gas recirculation valve are rough or misfiring idle, detonation, stalling and hard starting. The EGR valve is a component of an automobile...Apr 1, 2015 · Step 2 – Dirty throttle body. The throttle body itself might be dirty or damaged if the idle is higher than it should be. Typically, a dirty throttle body can cause a rough idle condition as the throttle plate cannot close properly. To fix this, first remove the air intake hose. It attaches directly to the throttle body. Yes, a faulty air control valve can cause hard starting. Whenever you start your engine and the car idles, the throttle is closed, leaving the IAC valve to meter the proper amount of air to allow into the engine and maintain combustion. If it lets in too little or too much air, hard starting and rough idle often ensues.Some of the more common symptoms of a worn-out or broken engine exhaust valve are rough idling, backfiring, reduced power and decreased gas mileage. In certain cases, this problem ...From vehicles to industrial tools, there are many products that use pneumatic systems. This means the system takes compressed air and uses it to control energy as it moves through ...ROUGH ENGINE IDLE. If you notice that your car is vibrating too much when parked with the engine on, then this is due to rough idling. A rough engine idling indicates that there is a bad idle air control valve. Since the engine is not receiving an appropriate amount of air when idle, the vehicle will shake intensely.

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However, a bad throttle body can allow the plate to open slightly at idle. This will increase the engine’s RPMs and cause the idle to be higher than normal. A high idle can be a sign of a bad throttle body, so you should not ignore that symptom. — Low Idle. On the flip side, a low idle can also be a sign of a faulty throttle body.Misfiring while idling. Another symptom of a bad or failing PCV valve hose is your vehicle will misfire while it is idling. This can be from a loss of vacuum due to the hose not working properly because of a leak, the hose being pinched, or becoming clogged from buildup over time. A misfire will sound like the engine has a vibration to it is a ...1. Check Engine Light Is On. The first sign of trouble for your canister purge valve is the check engine light. Your canister purge valve is controlled by your car’s computer, which allows it to monitor its performance. If your car’s computer detects higher or lower than expected purging from the valve, it will illuminate the check engine ...Bad Throttle Position Sensor Symptoms. 1. Engine Won’t Idle Smoothly, Idles Too Slowly, or Stalls. If you start to experience engine misfires, stalling, or rough idling when the car is stopped, it can also be a warning sign of a bad TPS. If it is a faulty throttle position sensor, you definitely don't want to wait to get this checked out.Valves are essential components in various industries and applications, playing a crucial role in controlling the flow of liquids, gases, or even solids. From regulating flow rates...

Yes, a faulty air control valve can cause hard starting. Whenever you start your engine and the car idles, the throttle is closed, leaving the IAC valve to meter the proper amount of air to allow into the engine and maintain combustion. If it lets in too little or too much air, hard starting and rough idle often ensues.Feb 12, 2023 · These are six of the possible symptoms you may notice when the Throttle Position Sensor (TPS) goes bad. 1. Check Engine Light. The Check Engine Light comes on when the TPS sends an incorrect reading to the computer. Because the TPS is monitoring the throttle plate, any malfunction will be registered. In today's video, we will look at the five common bad idle air control valve symptoms. We will also examine the IAC valve's function, location, and replaceme...There are several methods you can try to reset an idle air control valve, the simplest of which is to: Turn your vehicle on and leave it in park. Step on the gas pedal for 5 seconds. Turn the vehicle off. Wait for 10 seconds before turning the vehicle back on.It could also be due to a cracked vacuum hose, a seized caliper, a bad brake booster or contamination of the brake lines. 2. Trouble Braking. If the check valve is blocked, air can’t be sucked in from the vacuum brake booster. If it breaks, air seeps into the brake booster. Either way, braking performance is hindered.In order to reduce the potential of these serious situations occurring, listed below are a few warning signs to be aware of that might indicate a problem with the VVT solenoid. Here are a few symptoms of a worn out or broken VVT solenoid. 1. Check Engine Light is Illuminated.A bad PCV valve will affect the performance of your vehicle, so there are a few signs to watch out for before the valve completely fails: 1. Excessive oil consumption and leak. A bad PCV valve may have a leak, which will cause excessive oil consumption. In addition, you may also notice oil leaking through the seals and dripping on to the floor ...On fuel-injected vehicles, the idle air control valve attaches to the throttle regulating the airflow and ensuring smooth idling. When the throttle plate closes during idling, the air control valve bypasses the plate injecting …Misfires are another potential symptom of a bad air idle control valve. Misfires happen when there’s not enough air and fuel in the cylinder, causing incomplete combustion in the cylinder. You may also experience backfires, which are similar to misfires. A backfire occurs when the combustion takes place in the intake rather than in the cylinder.Expose the throttle body by removing the air duct. Look at the throttle body and locate the idle air control valve. It is a small opening in front of the throttle plate. Spray the throttle body cleaner inside the IAC valve and clean it with a soft wire brush. Reconnect the air duct and filter box.The rotary solenoid (RS) type IAC valve is located on the throttle body and intake air bypassing the throttle valve passes through it. In this way the intake air volume bypassing the throttle valve is regulated, controlling the engine speed. The ECM operates only the IAC valve to perform idle-up and provide feedback for the target idling speed.However with a bad IAC valve, this idling will be rough. You will experience heavy vibration (shuddering) when you idle the car. As the valve has gone bad, there will be no/very little air flow to the engine, when you idle the car. Thus, your car will shake, vibrate, and may also make a loud noise while idling.

Oct 10, 2007 · 28. Providence, RI. Dec 29, 2008. #2. sign of a bad iac valve would be stuttering. or at idle it could be idling like ****... i just swapped an IAC on my girls expedition. the truck would idle as if it was cammed out, and soon as you go to drive, it would stall. it COULD also be that your MAF is clogged.. my maf was clogged with a bunch of ...

Jun 22, 2013 ... Idle will be normal once the car is heated up and the IAC valve its unplugged. I have the same problem, took the IAC out blew air through and it ...Signs of a Bad Idle Air Control Valve An idle air control valve is, in a very real way, the predecessor to the drive-by-wire throttle systems commonly employed today. It performs much the same function as any electronic throttle: to control the amount of air going into the engine so the computer can match it with the right amount of fuel. ...Check Engine Light Comes On. Randomly Fluctuating Idle Speed. Rougher Engine Idling. Frequent Engine Stalls. Vehicle Backfires. How to Address the Issue. Step 1: Park Vehicle and Switch off Engine. Step 2: Determine the Exact …3. Whining noise while turning the wheel. A whining noise may also be present if your power steering control valve is failing. This noise is usually heard while you are turning a corner, or turning the wheel in general. Whining may also be heard at idle. No whining noises should be heard while the vehicle is turning, so this is a red flag and ...By having a fully functional idle speed control valve, the engine idle speed never goes below 900 RPM or above 1,100 RPM. 5 Bad Symptoms. If you have an idle speed control valve which is starting to go bad, then you need to replace it as soon as possible.Signs Of A Failing Idle Control Valve . Several signs could indicate a bad idle control valve. But, these symptoms may also show up due to other engine troubles. In that case, it’s best to have a mechanic inspect your IAC valve to ascertain if that’s what is causing these symptoms. Here are some signs that could give you a heads up about a ...Signs of an intake manifold runner control failure. A failure in the intake manifold runner control system can cause several problems. These are some of the most common. Illuminated check engine light: If the car’s computer detects a problem with the system, it will turn on the check engine light. Poor engine performance: An engine needs …It helps keep the wiring harness against vibrations that can get it off the sensor. Step 3: Remove the idle air control valve’s bolts or screws. Now, remove the bolts or screws used in holding the car’s idle air control valve in place on the block. Step 4: Hold the downward-pointing valve and spray the end.The idle speed isn't user-defined, but it is necessary to make sure the conditions are right for the ECU to control the idle speed. Fully warm up the car. Drive it around the block if necessary. Disconnect the electrical connector for the AAC valve. Turn the Base Idle Screw clockwise until the idle drops to about 650 RPM.

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When your vehicle’s idle control valve malfunctions, it can cause all sorts of issues for your car, and on some rare occasions, it will stall. Normally, a bad idle control valve will throw off a few signs that will alert the driver of a potential problem. The following reasons are the most common symptoms of a faulty idle control valve.Check Engine Light Activates. One of the most common symptoms of a faulty VVT solenoid is the activation of the Check Engine light. This warning light will illuminate on your dashboard when the engine control module (ECM) detects a problem with the VVT system. The Check Engine light can indicate a wide range of issues, so it’s important to ... Identifying Signs of a Bad Idle Air Control Valve. Recognizing the symptoms of a bad IAC valve can help you diagnose problems early, preventing potential damage to your engine. Some of the most common signs include: Rough Idling: One of the primary symptoms of a bad idle air control valve is when your car is difficult to start and once started ... The estimated cost of a purge valve replacement is about $155 to $170. The total cost is broken down as follows; parts cost about $112, and labor costs between $43 and $58. However, the location of the purchase of the parts and the replacement should be considered in case of a slight difference in the estimated total cost of the replacement of ...Usually in gear at idle or low speed. If I gave it gas, the noise usually went away, and come back at low idle again. It was very annoying. The problem was a bad Idle Air Control (IAC). How The IAC Works: The idle air control valve is located on the intake and is designed to adjust engine air intake at idle which controls the engine idle speed.Intense vibrations while idling or a rough idle ride might be due to an irregular amount of air flow and are other signs of a malfunctioning IAC valve. At its worst, a bad air valve might cause stalling. If your engine stalls, always visit a mechanic. It could be a sign of several major issues. The idle control valve will trigger the check ...The cost to replace a bad idle air control valve varies widely depending on what you drive. The cost of an idle control valve itself ranges between $50 and $100. From there, labor costs range from $70 to $300. Combined, it can cost anywhere between $120 and $400 to replace your idle air control valve.Symptoms of a Faulty Idle Air Control Valve. A faulty or dirty ICV can exhibit one or many of the following symptoms: 1. Unusual Idling Behavior. The IACV’s primary role is to regulate your car’s idle when the accelerator isn’t pressed. When the IACV is faulty, it may cause the idle speed to deviate from the ideal range, leading to rough ...MAF sensors are located between the air filter and the throttle body and are responsible for measuring the amount of air entering the engine.. Most vehicles have a hot wire MAF sensor. It has one heated wire and one ambient temperature wire. The microprocessor inside the MAF sensor measures the air entering the engine by maintaining the … The IAC valve repair costs on average around $120 to $500, while the components price ranges between $45 to over $400, but service is only about $70. Of course, labor costs are directly related to the technician’s hourly rate. This task would take little beyond an hour to complete, so don’t estimate a high price. Jan 11, 2016 · 3. Whining noise while turning the wheel. A whining noise may also be present if your power steering control valve is failing. This noise is usually heard while you are turning a corner, or turning the wheel in general. Whining may also be heard at idle. No whining noises should be heard while the vehicle is turning, so this is a red flag and ... ….

Signs and Symptoms of a Bad Idle Air Control Valve A failing IAC valve often exhibits specific symptoms that, if noticed early, can prevent significant engine damage. Key symptoms include rough idling, stalling, and erratic engine behavior.Jun 22, 2013 ... Idle will be normal once the car is heated up and the IAC valve its unplugged. I have the same problem, took the IAC out blew air through and it ...Nov 26, 2005 ... Would a dirty or faulty idle air control valve have any effect the firmness of power steering? I am having a problem with really stiff ...ROUGH ENGINE IDLE. If you notice that your car is vibrating too much when parked with the engine on, then this is due to rough idling. A rough engine idling indicates that there is a bad idle air control valve. Since the engine is not receiving an appropriate amount of air when idle, the vehicle will shake intensely.Idle speed fluctuations are typical signs of a bad idle air control valve. The idle air control valve is installed to keep the engine’s idle speed consistent. The IAC regulates the engine’s air intake. The machine may occasionally spin at too high or too low a speed due to irregular air intake.Mar 31, 2024 · So, one of the most common symptoms associated with a problematic valve is, irregular idle speed. The valve is programmed, to regulate and maintain the engine idle speed, at a constant rate. So, if the valve fails or has any issues, it can cause the idle speed to be thrown off. This may result in an unusually high or low idle speed. Irregular idle speed is one of the most prevalent symptoms of a faulty idle air control valve in a Honda Accord. The idle air control valve regulates and keeps the engine’s idle speed consistent. Therefore, the idling speed might be thrown off if the valve breaks or has problems. As a result, it can cause an exceptionally low or high idle ...Jan 5, 2016 · 1. Rough Idle. One of the first symptoms that a faulty canister purge valve may produce is a rough idle. In this case, you will notice the car running inconsistently while stopped or driving at low speeds. If the canister purge valve fails and sticks open, it will create a vacuum leak that can affect the engine idle speed and quality. I explain the issues a bad IAC (AIC) Valve can cause, I show you the location of it and how I replace the Idle Air Control Valve on this Chevy Impala with th...Feb 22, 2023 · The most common thing you’ll notice from a bad vapor canister purge valve is that you’ll get a check engine light that you weren’t expecting. While the symptoms can change depending on whether or not the valve is stuck open or closed, one thing that shouldn’t change is that you should get a check engine light. 2. Signs of bad idle control valve, Check Engine Light Activates. One of the most common symptoms of a faulty VVT solenoid is the activation of the Check Engine light. This warning light will illuminate on your dashboard when the engine control module (ECM) detects a problem with the VVT system. The Check Engine light can indicate a wide range of issues, so it’s important to ..., May 8, 2010 ... You have already tested it, if you unplug the idle speed solenoid and it stays running you have a bad idle speed solenoid. When you unplug a ..., Jun 6, 2012 ... Rough idle. High idle. Starting problems. Intermittent stalling problems., Unlike a lot of other engine components, the idle air control valve doesn’t have a service or replacement interval. But it will go bad over time due to wear and tear, and here are the symptoms to look out for: 1. Abnormal Idling Behavior. First and most obviously is that your car will idle in a weird way., Jan 28, 2011 ... Evo Engine / Turbo / Drivetrain - How to recognize bad Idle Control Valve??? - Is there a way to see that Idle Control Valve is bad by just ..., Code 15 means the coolant temp sensor is reporting the temp is stuck at -40*. This usually causes an extremely rich mixture or flooding and no starts. This could explain your surging idle. If this truck has the electronic transmission like a 4l60e or 4l80e the faulty coolant or tps reading will definitely affect the transmission. Coolant temp ..., From vehicles to industrial tools, there are many products that use pneumatic systems. This means the system takes compressed air and uses it to control energy as it moves through ..., Signs of a Malfunctioning IAC Valve Engine Stalling and Rough Idling. If you notice your engine stalling or experiencing rough idling, it may be an indication of a malfunctioning Idle Air Control (IAC) valve. A poor IAC valve can cause your engine to stall at idle or even while driving., In this video, you will learn 5 symptoms of a bad purge valve. Watching this video will help you diagnose whether it is time to replace your purge valve. You..., In today's video, we will look at the five common bad idle air control valve symptoms. We will also examine the IAC valve's function, location, and replaceme..., One of the most common symptoms of a bad idle control valve is erratic idling, usually caused by a sticking valve. You’ll be able to see any erratic idling on your rev counter with the needle moving up and down., The idle air control valve is responsible for controlling the RPM when idle. It essentially puts the engine in a relaxed state whenever the power is not needed. A vacuum leak may also cause low RPMs. When the idle air control valve goes bad, the engine will stall. It means it may abruptly stop working., Usually in gear at idle or low speed. If I gave it gas, the noise usually went away, and come back at low idle again. It was very annoying. The problem was a bad Idle Air Control (IAC). How The IAC Works: The idle air control valve is located on the intake and is designed to adjust engine air intake at idle which controls the engine idle speed., Key Takeaway. Symptoms of a bad or burnt intake and exhaust valves include a decrease in power and acceleration, trouble starting the vehicle, poor fuel mileage, burning smell, rough idle, valve noise, and backfiring. A burnt valve can be caused by issues such as improper sealing, overheating, faulty exhaust valves, carbon buildup, or …, Loss of Power. If a purge valve is not functioning correctly, it can lead to the vehicle losing power or stalling unexpectedly. This can be caused by reduced fuel and airflow in the system, resulting in misfires and power loss. Moreover, if the faulty purge valve completely blocks the engine, it cannot start or run., Step 2 – Dirty throttle body. The throttle body itself might be dirty or damaged if the idle is higher than it should be. Typically, a dirty throttle body can cause a rough idle condition as the throttle plate cannot close properly. To fix this, first remove the air intake hose. It attaches directly to the throttle body., There are several methods you can try to reset an idle air control valve, the simplest of which is to: Turn your vehicle on and leave it in park. Step on the gas pedal for 5 seconds. Turn the vehicle off. Wait for 10 seconds before turning the vehicle back on., Here are some key tips and useful information when monitoring the engine's RPM and idle air control valve: 1. Regular maintenance of your vehicle, including its idle control valve, can help ensure that your car runs smoothly and avoid costly repairs. 2. Pay attention to the engine's RPM when starting your car and when idling. 3. If you notice ..., 4) Poor Engine Performance. VVT has the ability to generate more power or save more fuel depending on the phase of the camshafts. If your VVT solenoid is experiencing issue due to a faulty oil control valve, you may notice a reduction in engine performance, as the VVT system may not be able to optimize the engine for peak power …, The most common thing you’ll notice from a bad vapor canister purge valve is that you’ll get a check engine light that you weren’t expecting. While the symptoms can change depending on whether or not the valve is stuck open or closed, one thing that shouldn’t change is that you should get a check engine light. 2., Locate the electronic connector holding the idle air adjustment valve to the throttle body and detach it. To modify the idling, turn the idle screw. To raise RPM, spin the screw to the left; to decrease RPM, turn the screw to the right. Reconnect the electrical connection to the idle air adjustment valves once the idle has been changed to aim ..., Irregular idle speed is one of the most prevalent symptoms of a faulty idle air control valve in a Honda Accord. The idle air control valve regulates and keeps the engine’s idle speed consistent. Therefore, the idling speed might be thrown off if the valve breaks or has problems. As a result, it can cause an exceptionally low or high idle ..., Method 1 of 3: Troubleshooting issues with the idle control valve. The idle control valve, also commonly referred to as the idle air control valve, is designed to control and regulate the engine idle speed, increasing and decreasing it as necessary to keep up with operating conditions. On most vehicles, this component is attached to the intake ..., Mar 26, 2023 · That means you’ll need to pay both parts and labor costs. The average replacement cost of an idle air control valve is between $200 and $600. The parts could cost anywhere from $60 to more than $400, while the labor is between $150 and $400. Of course, the labor cost really depends on the hourly rate of the mechanic. , Vacuum leaks that let air into the manifold can also cause a high idle speed. A defective idle speed control valve that is stuck in the extended or high idle speed position can also be the cause. 11. Lean Engine Condition. Another usual sign of an unclean or malfunctioning car carburetor is when the vehicle runs low., So, one of the most common symptoms associated with a problematic valve is, irregular idle speed. The valve is programmed, to regulate and maintain the engine idle speed, at a constant rate. So, if the valve fails or has any issues, it can cause the idle speed to be thrown off. This may result in an unusually high or low idle speed., The IAC valve repair costs on average around $120 to $500, while the components price ranges between $45 to over $400, but service is only about $70. Of course, labor costs are directly related to the technician’s hourly rate. This task would take little beyond an hour to complete, so don’t estimate a high price. , Vacuum leaks that let air into the manifold can also cause a high idle speed. A defective idle speed control valve that is stuck in the extended or high idle speed position can also be the cause. 11. Lean Engine Condition. Another usual sign of an unclean or malfunctioning car carburetor is when the vehicle runs low., When it comes to showering, having control over the water temperature is essential for a comfortable and enjoyable experience. One way to achieve this control is by using a thermos..., How can I tell if my idle air control valve is bad? If your vehicle is experiencing symptoms like fluctuating idle speeds, hard starting, stalling at stoplights, poor engine performance, or a Check Engine light, then there is a possibility that your IAC valve is failing., A lean condition can occur because of an IAC valve stuck open that allows too much air to enter the intake manifold. This can affect your vehicle’s performance and drivability in various ways. For example, it can cause hesitation, surging, misfires, backfires, loss of power, rough idling, or hard starting., Identifying Signs of a Bad Idle Air Control Valve. Recognizing the symptoms of a bad IAC valve can help you diagnose problems early, preventing potential damage to your engine. Some of the most common signs include: Rough Idling: One of the primary symptoms of a bad idle air control valve is when your car is difficult to start and once started ..., 28. Providence, RI. Dec 29, 2008. #2. sign of a bad iac valve would be stuttering. or at idle it could be idling like ****... i just swapped an IAC on my girls expedition. the truck would idle as if it was cammed out, and soon as you go to drive, it would stall. it COULD also be that your MAF is clogged.. my maf was clogged with a bunch of ...