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

[blue00]

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

Enough beating around the bush, guy.

 

[TotalCarnage]

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

One tidbit on Ford. They use platinum plugs, but they use different ones in each bank. I've seen this on my Explorer and two Taursus'. I have no idea why they do this.

 

[Opera House]

When a spark occurs, only one side of the two electrode contacts is worn. In the DIS ignition system the coil is in the center between the two plugs and they both fire at the same time. One in the compression cycle and the other side in the exhaust cycle. So at the factory they know which electrode will wear. When you buy new plugs, you don't know so they put platinum on both sides of the electrode (insulator tip and arm). In millions of vehicles it saves some money. Hey, at 100K it was still running. By 60K they can often show wear. If these look reallu bad, this is not a good candidate for BOSCH.

 

[95explorer150K]

Since everyone is leaning towards an IAC. I think we are all mislead. The IAC is not what is wrong with my truck. I have replaced so much crap that this is ridiculous. I have replaced the IAC, fuel Filter, and many other miscellaneous parts. I am just frustrated to no end this damn truck. I still spudder when hot and have a rough idle at times. Sometimes the truck runs great. I am so confused as to what this could be. I want a definate answer if someone has one let me know. Please Again it is one of the spuratic things. Does not do it all the time. Just when it wants too. No specific pattern. Thanks for hearing me vent.

 

[Brandons]

Some things i got no idea if theyve ben tried or perhaps mentioned

mass air sensor - is it dirty?
hows the fuel pump sounding? does it sputter as well when the engine has problems?
Any vacume leaks
Air intake leak

Again im not for sure about what it could be, but just in case i had to mention them, theyve all ben problems ive had.

 

[targee53]

IAC Cleaned - now working

I just wanted to give a big THANKS.

I do minor work on my truck but a friend directed me to this sight. In just a few searches and short reads I got to this thread. The PICs are great and the extra help from another thread that indicated that IAC is under the black SOHC cover. 7mm cover off. 8 mm IAC off. I used carb and choke cleaner and que tips to clean mine. I also removed the felt in the black cap during the cleaning. It had some particals (probably leaves) in the black cap. I also worked the plunger (gently) to insure it did not stick. A couple of hits of the IAC into my hand produced some blacks specks. Get the sides walls.

I also clean the two tubes in which the value connects to the engine with que tips sprayed with clean and then used dry ones. Re-installed IAC and bam my 98 XTL Explorer is running great. The first start went to 2000+ rpm but then quick adjusted to the normal 550-600 rpm.

FYI: My problem was truck ran fine night before and night was cold. In morning truck would not idle and stalled without gas pedal so I was forced to two pedal it.

 

[ions]

Found this post and decided i wanted to do it while i was washing my truck and i took off the IAC valve (no black thingy) and it is pretty black in there and bought some CDR Electric Parts Cleaner from Autozone for 2$ and i took off the IAC valve and it doesnt look anything like the valve in the pictures (i have a 2001 sport trac) and i was wondering do i just spray the cleaner in the valve and let it drain or do i have to do other stuff also? the can came with a spray hose so i can stick it in there and get in it pretty good but here are some pictures of my IAC

 

[spindlecone]

Found this post and decided i wanted to do it while i was washing my truck and i took off the IAC valve (no black thingy) and it is pretty black in there and bought some CDR Electric Parts Cleaner from Autozone for 2$ and i took off the IAC valve and it doesnt look anything like the valve in the pictures (i have a 2001 sport trac) and i was wondering do i just spray the cleaner in the valve and let it drain or do i have to do other stuff also? the can came with a spray hose so i can stick it in there and get in it pretty good but here are some pictures of my IAC

Depress the piston with your finger and you will find somemore carbon buildup in the cylinder also.
'Clean it, when all is dry put a drop of 3and 1 oil on the piston.

 

[aldive]

I was starting to get some "noise" from the intake on my '99 SOHC. so I decided to clean the IAC before purchasing a new one ( I got a quote from Torre at Ford Parts Network [ http://www.fordpartsnetwork.com/ ] - YU3Z 9F715-AA $ 67.99 plus Freight $ 7.99 ).

Th truck has 104k miles on it and this is the original IAC and has never been removed to clean before.

There is no black cap on my IAC.

Upon inspection of the IAC, there was very little black "crud" inside and no real buildup. It was much cleaner than I would have expected. I wonder if this has anything to do with regular intake dosing with Sea Foam?

I removed the IAC and sprayed the inside well with Electrical Parts cleaner and allowed it to soak for about 15 minutes. After throughly drying, I reinstalled ( using the original O ring gasket ).

The truck started immediately and ran smooth as silk with no more noise.

 

[aldive]

Here it is a month later and the noise and somewhat rough idle is back.

I decided to just replace the IAC and "gasket". It is a 5 minute job and a $90 part at my local Ford dealer. Part number is YU3Z-8F715-AA. New "gasket" was about $3.

Idles like new again. Sometimes cleaning is not enough and a new IAC is required.

 

[asnraccoon]

check engine light on

hi.. i'm new here.. from what i've been reading, i think i might have a similar problem.. i just got a 99 xlt with 90k on it. i had the 90k tuneup a couple weeks ago at 87k before i drove it cross country here to school. i had the throttle body replaced there b/c it was causin problems before.. and it seemed to do the trick temporarily.

now, it seems to have a really rough idle on cold starts.. the rpms start around 1k .. then jump to 2-3k.. then drop back down to 5-6 hundred when its not too cold out.. but now that its gotten cold again, my engine just dies if i don't manually keep the rpms up to warm up the engine. my check engine light also just came on and i have no idea why. ford wants to charge me 150 just to see what the problem is. any ideas before i spend more of my student loan money to fix my car?

 

[TPLYNCH]

Do you have the SOHC 4.0 engine? If yes, your symptoms are classic signs of back intake manifold O-rings. There is an extended warranty on them, but not sure if it is 100k or 75K. You can take the truck to an Autozone or most other chain autoparts store and have the codes read for free. Report back with those and we can confirm diagnosis, fixes.

If you have the SOHC Engine, you may want to search for and read up on all threads related to 00M12 and 01M01 programs.

 

[aldive]

hi.. i'm new here.. from what i've been reading, i think i might have a similar problem.. i just got a 99 xlt with 90k on it. i had the 90k tuneup a couple weeks ago at 87k before i drove it cross country here to school. i had the throttle body replaced there b/c it was causin problems before.. and it seemed to do the trick temporarily.

now, it seems to have a really rough idle on cold starts.. the rpms start around 1k .. then jump to 2-3k.. then drop back down to 5-6 hundred when its not too cold out.. but now that its gotten cold again, my engine just dies if i don't manually keep the rpms up to warm up the engine. my check engine light also just came on and i have no idea why. ford wants to charge me 150 just to see what the problem is. any ideas before i spend more of my student loan money to fix my car?

I have had similar problems and slowed them down with a through MAF and IAC cleaning, however, to finally fix, I just replaced the IAC.

Good luck .....

 

[asnraccoon]

thanks guys .. i'll have to find something out here and see whats up..
[edit]
so i went to autozone and got a engine code of p1506 which came up as idle air overflow error. they told me it was the idle air control valve and that it's 80 for the part. any suggestions?

also how would i know the o rings and other stuff need replacing since i'm pretty sure they wouldn't show up in the engine codes? i'm new at all of this and sadly don't really have the time or money to get my explorer up to tip top shape.. my goal in all of this is to keep it running until i graduate in like 3 years and have time and money to put into my car. : )

 

[TPLYNCH]

If after cleaning (or replacing if cleaning doesn't work) the IAC you still have the same symptoms, then you may need to look at the O-rings. Ford should be able to tell you if the O-rings, camshaft tensioners and timing chain cassettes have been replaced using your VIN #. The replacement part kit is not very expensive, and there are instructions with pictures in a thread on this site.

 

[ExplorerOfDaMud]

i know mine needs cleaned cause my buddy was tapping it with a hammer one night we were working under the hood and it started to idle alot smoother but then after awhile it would start to do the same stuff then wed tap it again and it would do clear up then go back after awhile so deff. sign of needing cleaned?

 

[Tony H]

I don't know how old this post is BUT
what wws the results with most of you guys who cleaned it but was waiting before starting?

Also,I have a '91 The IAC looks very close but a little different (no Black cap) I wonder if I should clean the gack out of the two holes and see what happens.
I'm real border line on my Emmisions and I wonder if this will lean it out a bit.

 

[ions]

My rough idle is back so im just gonna buy a new one (this one has lasted over 70K tho) and i have a question motorcraft has 2 SKU #s for the IAC for a 2001 sport trac and i need help on which to order? here are the #s if anyone can help me

CX-1791 Idle Air Control Valve] SOHC Eng.; XL2E-9F715AB
CX-1915 Idle Air Control Valve] SOHC Eng.; 1L5E-9F715AB

Thanks.

PS. The 1791 picture looks like the one on the first page so i think i ordered the right one (the 1915) but im just making sure.

 

[asnraccoon]

so i cleaned it out the iac with electrical cleaner like some of you recommended.. idles fine now.. but it hasnt' been that cold out so kinda hard to tell on first start. so i was wondering for those of you who replaced the iac.. did the check engine light turn off automatically or did you have to reset the computer?

but the check engine light is still on and i'm still limited in my revs to 3500 .. even when i turn the od off. any suggestions?

 

[aldive]

What code is causing the illumination of the CEL?