IAC Valve Testing?

[281Thunder]

Ok so after getting my car up and running again from a few weeks ago, it's been running great since then, no problems at all. Wednesday morning I drove it home from work, ran perfect. I went to get in it yesterday morning, started it up, it died. Repeated this for a few minutes. It'll start up for a brief second then die. If I give it gas it'll run perfectly smooth, and I can hold it steady at 1000 rpms with the pedal...smooth as can be.

I'm leaning towards the IAC valve right now, since as soon as you let off the pedal, it dies immediately. Is there anyway to test if it's working properly? Last I checked they're kinda pricey and I don't wanna blow a bunch of money if I don't have to. Any other thoughts that it could be? TPS maybe? It's not throwing a CEL, not sure that it would since it won't run long enough to. I've got a datalogger I could hook to it, but again, when the car dies the datalogger shuts off. Any help is appreciated.

 

[LauraSVT]

It won't kick a light. You may get a code, though. Regardless, your best bet is to pull the IAC out of there and spray the hell out of it with Berryman's. Be careful of your eyes, as the Berryman's has a tendency to shoot out one side of the valve as you spray the other. Go nuts and cram a sponge in there to clean it out further if you like. I'd eschew Q-tips, as the lint is problematic. Let it dry completely, and reassemble. This should work well. If it does not, it's a good indication that it's time for a new IAC valve.

 

[SoopaCooga]

I believe the TPS would throw a CEL, but the IACV won't. IACV go for $25 at Advance Auto Parts. You could return it if that doesn't fix your problem. :shrug:

Something else to consider: Did your battery die recently or was your PCM reset? If so, recall that it takes a couple of trips for the PCM to relearn how to idle.

 

[281Thunder]

Thanks guys, I'll give the cleaning a shot. It's just mysterious to me as it started out of nowhere.

Battery's been fine and my Autometer still shows around 14 volts usually. It's been running good for 3 weeks since the battery was unhooked so I'd think it would've shown itself sooner than that.

 

[LauraSVT]

Thanks guys, I'll give the cleaning a shot. It's just mysterious to me as it started out of nowhere...

That is the only way it seems to happen -- out of nowhere. My unscientific experience seems to indicate that the probability of it happening is higher if the car has been sitting for a spell. Sure is theater firing it up and, if you're bold, actually moving the car in that condition. You sure have to prime the piss out of it to keep it from stalling. Wakes the neighbors. :laugh:

 

[281Thunder]

Heh, it's not quite loud enough to wake the neighbor's...they're a hundred yards away or so. Now if I were to do it in the Tbird...that'd be a different story lol...

 

[sav0320]

My parents Fukus ZTW would stall after long drives on the freeway. A little throttle could keep it running. Ran it on an NGS and no codes. Definitey seemed like IAC. Replaced IAC, no issues again. You'd think something would be set for emissions, but maybe not.

 

[Silver Bullet]

I believe the TPS would throw a CEL, but the IACV won't. IACV go for $25 at Advance Auto Parts. You could return it if that doesn't fix your problem.

More like $100 for IACV at Advance or other local auto parts
Even Rock Auto is $80 but then must add $10 or more shipping
Cleaning is definitely worth a shot first

 

[TUFTOUR]

Bill Jenkins at Team Ford can get it to you for around $74...I actually just bought one this week.

I've heard cleaning is a bad idea...it tends to dry out the seals in the valve, causing continued problems and is ultimately only a temporary fix...

 

[Big Jim]

Bill Jenkins at Team Ford can get it to you for around $74...I actually just bought one this week.

I've heard cleaning is a bad idea...it tends to dry out the seals in the valve, causing continued problems and is ultimately only a temporary fix...

Then mine must be at the brink of failure. I've cleaned it several times during my car's life. 245,000 miles of trouble free driving.

It is most certainly worth trying to clean before replacing.

 

[281Thunder]

Actually, looks like the local Advanced/Autozone has them for around $55-$60.

Just haven't had a chance to mess with it. Had other things to do the past few days, worked all day tomorrow, then heading to MIR tomorrow for import vs. domestic.

 

[281Thunder]

Picked up a new IAC this morning, figured at 147k miles I might as well get a new one. Took 5 minutes to install, fired right up and idled perfectly. Thanks for the help!

 

[SoopaCooga]

sweet!

 

[281Thunder]

Very sweet...and in good timing too. I had been driving the Tbird for the past few days while the Contour was down. Coming home from a friend's last night, the cooling fan motor decided to lock up tight. I pulled into a parking lot with smoking rolling out of the vents in the hood. Got it unplugged and headed home. Luckily it was cool outside and I didn't get slowed down much.