Fast Idle Valve Solenoid [Archive] - Forum


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10-01-2008, 04:39 PM
What is it?
Do we have one?
Where is it?

Would it throw a P0507 code?

10-01-2008, 10:23 PM
Never heard of it.
We don't have one.
We only have one idle air control valve (IAC) in the top of the throttle body, that opens and closes to let air around the throttle plate and control idle speed.

P0507 is for idle speed high. Basically the pcm references a bunch of other sensors and uses them to determine what the desired IAC position is. If it notices the idle speed is 175 rpm above or more than the desired idle speed with the IAC at it desired position for the reference, then it sets the code.

Most common causes are blockages or build up of residue in the intake or TB, a large vacuum leak, or a faulty IAC valve. Check to make sure your air filter is clean and there isn't any debris in the intake or in the IAC hole in the TB on either side of the throttle plate. You might need to take the TB off to do this, and you'll also want to check the back side of the TB bore, plate, and IAC hole for residue or carbon deposits. Clean it if it's dirty. Might want to take the IAC out of the TB and clean it and the hole out with some brake clean, to make sure it's not sticking in the hole.

If that doesn't fix it, start checking for vacuum leaks. If you don't find any, try replacing the IAC valve. That should fix it.

10-02-2008, 06:23 AM
The CAI, TB, and UIM are all brand new from MPR. I replaced the TBS and IAC. I have not found a vacuum leak so far, but I know it's got to be there some where. I am going to buy a new MAP tubing/vacuum line from the dealer today. I sounds like there might be a hissing coming from that area. Start with the cheapest stuff. I have had this problem well before I did my rebuild, so I am trying to look at all the original parts that I have not replaced.

As for the Fast Idle Valve Solenoid... I found a few site that sell it for our cars, but I have never seen it, or heard of it. I found out the it is usually located near or around the TB...and I know it's not there on our cars. I just wanted to make sure I was right.

10-02-2008, 04:25 PM
They probably mean the idle air control valve and just call it something else. It might be called that on other cars, or other cars might have a different type of valve. But yeah, if all that other stuff is new and clean, then I'd suspect a vacuum leak first. Then the IAC valve itself if the problem persists.

gagt Mechanic
10-02-2008, 10:15 PM
buy carb cleaner and start to spray your vacume lines, uim, and tb. increase in rpm=leak

10-03-2008, 06:30 AM
Saw it on

I have already replaced the IAC. I sprayed some carb cleaner near the MAP sensor and seemed to idle slightly different. I ordered a new vacuum line for that at the dealer yesterday. I'll put it on today, and see how it goes.