How to: IAC valve cleaning thread (w/pics)

[karl_burns]

Any CEL?
Maybe check the intake tube and make sure everything is in working order. If there's a small hole, and it's not a vaccuum in there, your engine could idle funny / die.
Karl

 

[95explorer150K]

Thanks Karl I will also check that out. The X has over 160,000 miles on it. Any other parts needing any attention too? I have replaced so many parts on it. It was worth it though.

 

[skyward]

I also went a step futher and cleaned out the throttle body and intake plenum(fun) and man were they filthy!
It was like hardened sludge in there and it took about a full can or carb cleaner to do the job. I think i'm being to liberal when I re-oil my air filter, I've heard not to oil it too much...any thoughts or opinions on that? I also replaced the PCV and with all that done, my truck runs like a top. If my intake plenum looked that bad, I hate to see what my intake manifold looks like.

Here's an excerpt from my Explorer Haynes manual. This is a caution at the beginning of the IAC valve check and replacement section. "The throttle body on these models is coated with a sludge resistant material designed to protect the bore and throttle plate. Do not attempt to clean the interior of the throttle body. The throttle body is designed to resist sludge accumulation and cleaning may impair the performance of the engine."

 

[urbanistic]

hehehe

 

[DB_1]

Yeah, I saw the little sticker on the throttle body that says that too but the TB was so carbonized or dirty that I figured clean would be better than leaving it dirty. I haven't noticed a lack of performance at all. Ford strongly recommends that you do not modify the suspension or put on larger tires but how many of us pay any attention to that?

 

[Rob0424]

I seem to be having the same problem as alot of you. When I start my engine I need to give itsome gas in order for it not to stall out. It had only been doing it intermintantly, but the last couple of days it had been doing it alot. Then today the Check Engine light came on, and I had it tested and came out with a DTC code P1507, which has to do with the IAC. Do you think cleaning it willtake care of this problem and make the check engine light go off?

 

[DB_1]

Cleaning the IAC would be the first thing i'd do, it only costs you a can of electrical parts cleaner and you have nothing to lose. Worst case scenario is that you have to buy a new IAC which isn't incredibly expensive.

 

[urbanistic]

First, check the vacuum hoses. Prolly a loose one to the idler... or a plug came off. Second, go to your local parts store and get a code reader. Your PCM can tell you more on what is wrong than any of us. They sell a Ford code reader for about 30 bucks. Use it.

Your check engine light can be caused by a number of sensors going bad, or even vacuum problems. Get the code reader. If your O2 or IAT is shot, this will tell you so. Also, if your IAC is shot, the code tester will tell you as well. You may even need a new purge solenoid.

Once I made repairs to my 4.0 after using the reader, the ***** runs like when I first got her.


A side bet, Im guessing a missing vacuum plug and a bad IAT.

 

[95explorer150K]

Well My IAC is very dirty. I cleaned it and it seems to make the problem worse. So I am thinking I should buy a new IAC. Does rockauto have the part number for a '95 explorer? My IAC has over 160,000 miles on it. Do you guys think I should replace it. Thanks a bunch.

 

[95explorer150K]

Still Spuddering!!!

I replaced my IAC and it is still doing the spuddering. I drive it all day and it runs fine. But when I let it sit for an hour and go back out there to drive my '95 X it will not idle at all and sometimes it will die. Sometimes it will run somewhat and sound like it is going to die. What else could be wrong. I have no check engine light on. I have read the forum about this topic and no success on fixing this. My X has 160,000 miles on it. Other then this problem it runs great. Any ideas? Let me know. Thanks.

 

[Brandons]

Did you also check other things like the spark plug condition, air filter, easy crap like that?

Just in case ya overlooked it

 

[DB_1]

Did you also check other things like the spark plug condition, air filter, easy crap like that?

Just in case ya overlooked it

I was just gonna say that too...you never know when the previous owner changed them last or at all. Are you getting a rough idle? How is it driving around town, does it feel like it's lagging at all? Could also be Cat. converter or muffler issue.

 

[Brandons]

Yeah i had a simmilar problem, when i started getting into working on the truck, my parents of course bought it new and own it still, it was getting a really rough idle and lagged when you gunned it, dad said the mechanic told him they were platinum plugs, which the guy also told him would last 160000km, of course i was like, something is really wrong there, a factory vehicle with platinum plugs... i checked and it was the basic plugs, really worn away and i was seriously amazed the truck still ran. We put new ones in and it ran mint.

PS the plugs were 120 000km on them then

 

[Brandons]

I agree especially with the catalytic convertor part. And tons of other things could do it too.

 

[95explorer150K]

Well guys I have been posting about my coolant gauge problem hit this link if you want to read it:

http://www.explorerforum.com/forums/showthread.php?t=99655&page=1&pp=20

I am so confused on why I have all these problems. I swapped the fuel filter as soon as I got the truck back. I am still have the same ideling problems. Mike we still on for this weekend for lunch? It spuddered again yesterday. I have to hit the gas in order for it to catch on. I am going to the shop tonight to mess with the my gauge cluster and will keep you guys updated on changes.

 

[Espresso]

95explorer150K, i'm havin the same problem on my 94. At first it was just when I filled it with fuel. But just today I went & got some detailing stuff. I came home & parked it. Tokk about an hour to do the tires, wax, ect. Went to start it.. Stumbling, could barely move. So I did like I normally do. Let it sit for a minute & viola..it starts right up, with no problem.
It isnt the fuel filter, air filter. I just put in a new PCV valve. I do honeslty believe it has to do with the evap system.
I'm not getting any CEL..nothing just an intermittent idle problem. That will cur eitself everytime if I let it sit for a minute after trying to start it.
Maybe its the canister solenoid valve( that would through a CEL though right?).
I dunno. I havent worked on these since they were new back in 93-94. But i'm determined to find the problem very soon.

 

[urbanistic]

Try checking your purge solenoid.

 

[95explorer150K]

I am narrowing it down to the fuel system. Possibly an injector is leaking or maybe it could be the Fuel Sending unit. Could be going bad? Any feedback? Let me know. Thanks.

 

[97headache]

Enough... just change the damn IAC! It's a $50.00 part held on by two bolts. Do that first, then go from there...

 

[karl_burns]

97:
To defend the people asking questions in this thread, the IAC is only recently a $50 part form AutoZone (or wherever). Years ago, when these questions first arose, the IAC was a dealer-only part listing for like $135. Much different scenario.
Karl