The idle air control valve is otherwise known as an idle air control actuator. It handles the rotational speed of an idle engine.
What is even more interesting is that the idle speed is not the same all the time. Several factors such as load to the electrical system and temperature contribute to how slow or fast the idle speed is.
What happens when it goes bad?
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. The effects usually gradually worsen in time. It may start with one to two stalls in a week and may worsen to three or more per day. Are you experiencing engine stalling on the road?
Give your engine a break by switching off the air conditioner.
Here’s a real-world example. You are at a stoplight, and there are still 60 seconds left at the stop sign. If you lift your foot from the pedal, your engine will go on idle. If you have a bad IAC valve, it may abruptly stop working instead of going on idle.
To avoid any complications, consult a professional mechanic as soon as you experience at least one of the six symptoms. Find out what the symptoms are of a bad IAC valve. Doing so should save you from the possibility of spending more money.
Can you drive anyway?
Yes, you can still drive with a bad idle air control valve. However, the more pressing question is should you drive a car with a bad one?
Driving with a bad component is not advisable, especially not this one. A bad valve will cause your engine to stall, detrimental to your and your passenger’s safety.
It’s also important to know that a bad one could lead your vehicle to fail an emissions test. Park your car and figure out what your next move is to avoid full on failure.
How do I reset it?
There are a few reasons why you need to reset the valve. One common reason is the need to recalibrate it. Another reason to reset it is to make sure that the check engine light is not on by mistake.
Performing a reset is easy and takes a maximum of one minute. First, slightly press the accelerator pedal just before ignition.
Then ignite your engine and leave it running for five seconds. Once that has passed, switch off the engine and wait for about ten seconds. Lastly, ignite your engine again and check if it is idling normally.
Suppose you have done the reset and are still facing issues with it. In that case, it is best to consult a mechanic for professional advice.
Is it stuck open?
If stuck open, it will operate as expected once it reaches an optimal RPM. When the engine starts from a cold state, it may shut down once a small puff of smoke goes out of the exhaust pipe. It is the result of an obstructed component.
Hopefully, this article has given you a better idea of how to deal with an engine showing symptoms that need to be addressed. That pesky engine light may be an indication of system errors. It could also be that the IAC valve is starting to act up.
You may test it in various ways. You can even have it cleaned. It’s important to know that there comes a time when a replacement is probably inevitable. However, if you’re cleaning it, make sure the throttle position sensor stays in place.
Here is a list of the cars and manufacturers that seems to have a significant number of bad IAC valve cases. You should particularly be looking for the symptoms with any of these cars:
- 1998 Dodge Ram
- Dodge Dakota
- 2000, 2001, 2002, 2003 Honda Accord
- 2000 Honda Civic
- Ford Explorer
- 1999 Honda Accord
- Jeep
- 2003 Chevy Silverado
- 94 Chevy 1500
- 2000 Nissan Maxima
- 4.3 Vortec
Whether you have a Miata P0505, it’s important to find its location and see what is going on.
Can a bad one cause hard starting?
Yes, a faulty valve can cause hard starting and rough idling. Make sure to check it out. As you can see above, most of the reported issues that we were able to find were with older vehicles. You shouldn’t let the fear of such a small component be something that worries you! Replacing it won’t be a major expense.
There will be times when you need to fix up a bad air control valve when the car isn’t idling at its best. That is when you need to do the following.
Have you noticed any of the following symptoms indicating a potentially failing idle air control valve?
- A vibrating feeling
- An idle engine sound is rougher
- The idle speed fluctuates
- The check engine light coming on.
