IAC repair Help
New User
Joined: Aug 2003
Posts: 22
Likes: 0
We are having similar problems with what we are pretty sure is the IAC valve. We did the cleaning a year ago and that helped. At this time it was so erratic it was stalling. Then we recently replaced it because it was idling low and erratic. We had disconnected the battery for a long time as well. It is still running low at idle which is causing vibration. Someone in another thread mentioned about changing the setting on it by turing the screw 1 1/2. Could you please elaborate on how to do this... Should we start the truck and disconnect the IAC, reconnect and turn it until the idle is where it should be, while the engine is running? Then let it idle for 15 minutes?
Posting Guru
Joined: May 2002
Posts: 1,574
Likes: 1
From: Phoenix
Not sure about IAC adjustment. I haven't looked for it but I do know the PCM program tells the IAC to open or close to maintain a set idle RPM. There are various conditions that the PCM loks at to determine the right idle speed. But it should not go below ~650 at any time. If the controls and evices are doing everything they can and are operating correctly, then some other mechanical issue is not allowing a smooth idle. maybe as simple as a vacuum leak. Do you have and CEL codes?
New User
Joined: Dec 2005
Posts: 1
Likes: 0
Cleaned IAC Value
Thanks to all,
Only 10 mins. of work and Explorer back to idling as normal. Removed IAC value filled bottom half with WD-40 and let sit overnight. This morning I cleaned the enter parts with a q-tip making sure not to get any of the WD-40 in the top half. Replace IAC value started up and bam idle kick in as normal. The IAC value was the problem.
Only 10 mins. of work and Explorer back to idling as normal. Removed IAC value filled bottom half with WD-40 and let sit overnight. This morning I cleaned the enter parts with a q-tip making sure not to get any of the WD-40 in the top half. Replace IAC value started up and bam idle kick in as normal. The IAC value was the problem.
New User
Joined: Jan 2006
Posts: 1
Likes: 0
Mountaineer IAC
Yeah, I had the same problem but seemed to solve itself.
however having had the experience of the "one foot on gas, the other on brake' I have no desire to repeat it so will replace the IAC.
One problem. I enter IAC for the search on all the auto supply web sites and get the not find message.
What am I missing?
however having had the experience of the "one foot on gas, the other on brake' I have no desire to repeat it so will replace the IAC.
One problem. I enter IAC for the search on all the auto supply web sites and get the not find message.
What am I missing?
New User
Joined: Mar 2006
Posts: 7
Likes: 0
Hi all... my first post on the forum... glad to be here! :-)
Recently picked up a 2001 Explorer Sport and have had an idling issue... when the A\C is on and its in drive, the idle drops way down... sputters a few times then dies. This only happens when its NOT in Park or Neutral. I'm going to replace the IAC valve as soon as the part arrives from Rockauto... (thanks for the terrific post and all the helpful info!!!)
Does anyone have any other suggestions, if this doesn't solve the problem ?
Thanks in advance!
Recently picked up a 2001 Explorer Sport and have had an idling issue... when the A\C is on and its in drive, the idle drops way down... sputters a few times then dies. This only happens when its NOT in Park or Neutral. I'm going to replace the IAC valve as soon as the part arrives from Rockauto... (thanks for the terrific post and all the helpful info!!!)
Does anyone have any other suggestions, if this doesn't solve the problem ?
Thanks in advance!
Junior User
Joined: Aug 2004
Posts: 76
Likes: 0
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Elder User
Joined: Oct 2003
Posts: 504
Likes: 0
From: Gilbert, AZ
Originally Posted by sbdivemaster
Hi all... my first post on the forum... glad to be here! :-)
Recently picked up a 2001 Explorer Sport and have had an idling issue... when the A\C is on and its in drive, the idle drops way down... sputters a few times then dies. This only happens when its NOT in Park or Neutral. I'm going to replace the IAC valve as soon as the part arrives from Rockauto... (thanks for the terrific post and all the helpful info!!!)
Does anyone have any other suggestions, if this doesn't solve the problem ?
Thanks in advance!
Recently picked up a 2001 Explorer Sport and have had an idling issue... when the A\C is on and its in drive, the idle drops way down... sputters a few times then dies. This only happens when its NOT in Park or Neutral. I'm going to replace the IAC valve as soon as the part arrives from Rockauto... (thanks for the terrific post and all the helpful info!!!)
Does anyone have any other suggestions, if this doesn't solve the problem ?
Thanks in advance!
New User
Joined: Mar 2006
Posts: 7
Likes: 0
Originally Posted by 4.0 Beast
is this only when the truck is first turned on and NOT warmed up, or is this at normal operating temperature.....?
I have the IAC on order and it should be here tomorrow. Hoping this solves the problem.
New User
Joined: Mar 2006
Posts: 7
Likes: 0
New IAC didn't help... 2001 Explorer Sport
Hi All,
I replaced the IAC following the instructions in the original post and the Explorer is definitely idling better but it didn't solve my issue and I'm looking for some other ideas.
Here's what's happening... whenever I have the AC or heater\defrost on and put the X in drive, the rpm's drop... sputters a few times... and then dies. If I give it some gas or put it in neutral (or back in park), the rpm comes back up and it idles fine.
It doesn't seem to matter if the X is warmed up or not. It died on me coming off the freeway after a 30 minute drive in 70+ degree weather.
Any thoughts ??
I replaced the IAC following the instructions in the original post and the Explorer is definitely idling better but it didn't solve my issue and I'm looking for some other ideas.
Here's what's happening... whenever I have the AC or heater\defrost on and put the X in drive, the rpm's drop... sputters a few times... and then dies. If I give it some gas or put it in neutral (or back in park), the rpm comes back up and it idles fine.
It doesn't seem to matter if the X is warmed up or not. It died on me coming off the freeway after a 30 minute drive in 70+ degree weather.
Any thoughts ??
Posting Guru
Joined: May 2002
Posts: 1,574
Likes: 1
From: Phoenix
Is this the 4.0 SOHC motor? If so, you might be having the intake gasket leak problem. Runs lean at idle and when you load up the motor with the electrical draw fan belt draw from the AC compressor, it throws it over the top and dies.
Question on temperature is that this problem is more noticable when cold and as the engine seats up, the intake gaskets seal better.
Did you get any CEL or have you check for codes. P0171 and P0174 are common for this issue.
Other possibility is a poor or marginal battery or alternator that can't hanlde the AC compressor load at just idle. Could test your charging/battery system.
Question on temperature is that this problem is more noticable when cold and as the engine seats up, the intake gaskets seal better.
Did you get any CEL or have you check for codes. P0171 and P0174 are common for this issue.
Other possibility is a poor or marginal battery or alternator that can't hanlde the AC compressor load at just idle. Could test your charging/battery system.