Where is the IAC valve?

[andypinto]

Hi there!
My 2002 4x4 4.0 SOHC V6 engine is experimenting a little rough idle, and stalls (undes 500 RPM) when the AC clutch engages. After a brief search in other forum's threads I realized that the IAC valve could be responsible for that.
I know where the IAC valve is in my old 1992 Explorer (running just fine with 180 K miles on it), but I don't have a clue where is in the new engine.
Anybody can help me about this, please?
Thanks all and happy rides!

Andy

 

[ditchwitch1]

HI,Pull off the plastic cover that says "4.0 "on it,4 8mm bolts,top of intake,IAC is right under this ,again,held in place by 2 8mm bolts,silver cylinder looking thing with wire harness plugged into it.Try cleaning shaft inside with 2+2,also,wouldnt be a bad idea at this time to clean throttle body too.It removes with 4 10mm head bolts{careful not to drop them into the great abyss}once removed,spray the blade and bore w/2+2,and using rubber gloved finger,scrub away the carbon&crap.I did both of these and picked up 3mpg.and somewhat smoother idle.4.0's arent known to purr anyway,also check EGR valve for carbon,dont get 2+2 on diaphragm,do cleaning with valve upside down,use a vacuum pump to pull it open,and clean seating area.I did this today,and it brought idle from a scary 500,to 650 rpm's Which drastically helped to smooth it out.Sorry about the long response,but Hope it helps! Good Luck,Kurt.

 

[andypinto]

Kurt, thans a lot for the complete info.
I'm sure that it helps!

Happy Rides

Andy

 

[ditchwitch1]

Hey Andy,Your welcome!Glad I could help.Have a great weekend!Kurt.

 

[ditchwitch1]

Update on my 98 eddie bauer

After living with a choppy idle for a week or 2,and addressing what seemed like all the possible likely causes,plugs,wires,cleaning throttle body,EGR,IAC,seafoaming 2x,with some improvement,I finally got under truck and changed the fuel filter{old one,when drained into a clear soda bottle,looked like milk with sand in it!}Lo and Behold!It runs like a new truck again,good starting,smooth idle,better mileage,whiter teeth,fresh breath,all that good stuff!As a mechanic,I sometimes overlook the obvious,forgetting the old saying..."K.I.S.S"keep it simple stupid!.While many of you out there may be experiencing the same problems,with a different cause,Go for the cheapest first,it may just fix the problem.I'm going out to wax her now,I like my truck again.

 

[andypinto]

Rough Idle problem solved!

Well, I following the instructions posted in this thread and finally found the IAC valve. The thing was really dirty so I use a lot of shots of 2+2 trying to get a deep cleaning. Also clean (very carefully) the MAF with a cottonswab and denatured alcohol, because look dirty too, as I did with the throttle body (with 2+2).
All assembled again, start the engine and voilà!
The idle is now just fine and the engine has no stalling whatsoever when the AC cluth engages.
Final cost? One a half hour of my time and few bucks in 2+2 and denatured alcohol.
Thanks God for the forums!
And Thanks a lot Kurt for the advice and have allways happy rides.

Andy.

 

[ditchwitch1]

Your welcome Andy!Glad it worked out well for You,Maybe it will help others too!Kurt.