The IAC was replaced, and the problem is worse.

[camcam]

Hello, I have been working on solving my idle issue for a few days now. I started by replacing the PCV, which was due, that didn't help, then I checked for vacuum leaks, no sign, then I found an elbow vacuum hose that was shot, replaced, still had issues. I then cleaned the IAC, it helped thought I fixed the problem, drove around, turned off, then drove again about 20 min later problem came back and then proceeded to get worse. I figured it was time based on all the information I gathered it was the IAC. I picked it and installed it. Started it up, ran for a minute or so, sounded good, then the idle went back to up and down and the whinning started which I read about but wasn't there before, and the idle is even worse now. I am at a loss and frustrated. My car is due for spark plugs, I wonder if this could have fouled them or might have something to do with it.

I look for some great help and support as I just joined, but have read threads for sometime now. thanks to all that have already helped me.

Thanks,
Cam

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the stock 2002-2005 section. Try a new IAC.

 

[waskly]

so what exactly is the truck doing?

does it idle, high, low, jumps erratic?

 

[swetrid]

It could be intake gaskets?

 

[not8taxi]

i have the same issue with my 02 ex...i posted a thread about it a few weeks back...the rpms would jump up and down at idle and eventually shut off...when i slow down to stop at a light or sign it sometimes shuts off also...i was thinking maybe my throttle body?...maybe a gasket? im going to be taking everything apart this weekend coming up ....let me know if you find anything

 

[not8taxi]

It could be intake gaskets?

if the intake gasket is leaking would there be any type of fluid coming out?...only reason im asking is because i noticed the other day an oil stain coming from the back of my motor from the intake manifold running to the back and bottom of the motor

 

[camcam]

Optimistic IAC is working

I didn't touch it today, just had to get away from all the diagnosing and work on the darn thing. I did start it up, wanted to check the air filter by taking it out, and it seemed to be acting up at the beginning, but the idle was consistant, around 1000 rpms, I let it warm up, then took it for a drive. It stayed consistant and did not go erratic like before, which to answer the question asked yes it was jumping erratically high then low then high then low with a sucking sound on the low end. I did read a thread either here or somewhere else about needing to reset the computer, when the IAC is replaced it the computer doesn't know the levels. That said, I think it might be okay now. I will drive it tomorrow, and I plan on changing the fuel filter and spark plugs - it is time for those anyways. Wish me luck, and if it acts up again I will be back.

 

[camcam]

not8taxi - did you change the IAC? The reason I ask, after checking for vacuum leaks and changing the PCV, the IAC was the one thing that was consistant to all the posts I read, here and in other places. My explorer has 104k miles and at 100k the book says to change the PCV and the Spark Plugs. So I started with the PCV hoping it was it. Funny, there was a thread I found with pic's regarding the PCV, I believe there are two PCV, one is on the left and the other is on the right, one has a filter mechanism on it the other is hollow.

 

[jstorm001]

This might sound crazy but when i replaced my battery on my 2002 explorer i had very bad idle i didnt know what was going on i check all the hoses & even changed my spark plugs which where only about a year & half old even did i oil change because i put this oil additives in thinking it was that but i still had a bad idle felt like it was going to stall i was going nuts over this problem so i didnt drive it for like a week or two. I read online somewhere the computer has to relearn the idle & shifting when the battery is disconnected so i said to myself let me disconnect the battery for about 15 minutes and i was shocked it WORKED!!!!! it fixed my problem still cant believe it was the new battery put in lol maybe same problem your having?? maybe....

 

[camcam]

I drove it around, it was fine for a bit, then started up again. Not sure if the new IAC is bad, not the problem, or if it is my MAF. I am trying the battery disconnect right now. I changed the air filter. Haven't messed with the fuel filter and spark plugs yet, that is going to be a task. It was mentioned might be intake gaskets, where exactly might those be - I am learning as I go with some of this. Thanks.

 

[camcam]

That didn't work. But I did unplug the IAC and started it up. The idle was low but consistant. Does anyone know if that is telling me I might have a bad IAC? FYI-it is a brand new IAC installed.

 

[not8taxi]

not8taxi - did you change the IAC? The reason I ask, after checking for vacuum leaks and changing the PCV, the IAC was the one thing that was consistant to all the posts I read, here and in other places. My explorer has 104k miles and at 100k the book says to change the PCV and the Spark Plugs. So I started with the PCV hoping it was it. Funny, there was a thread I found with pic's regarding the PCV, I believe there are two PCV, one is on the left and the other is on the right, one has a filter mechanism on it the other is hollow.

i have the 4.0 so i dont know if theres 2 pcv but i did change it at about 90k...my truck currently has 105k...i replaced the iac...left the mechanic and a minute later at the light the truck died...brought it back to him and said maybe the iac is no good...so he ordered me a new one and put that in...still the same thing...fuel filter was replaced less than 1k ago...i tried fuel injection cleaner...thought it made it better but it went back to acting up after a while of stop and go traffic....and to clear it up the CEL has not come up on the dash...everyone else on here that has a rough idle problem i think had the CEL come up and diagnosed the problem with that...

 

[not8taxi]

just asking this but does the tps sensor on the throttle body itself affect the idle in any way?...im guessing this would throw a CEL ...

 

[irocdupi]

This might sound weird but try running the car without the mass air flow sensor plugged in. My grandfathers 93 Buick Lesabre broke down over the weekend, would stay running revved up but not at idle. So I changed the fuel filter still didnt run, did plugs and wires, still nothing, changed the fuel pump still no improvement. Took apart the intake, throttle body was dirty cleaned that and nothing. Disconnected the mass air flow sensor after, and it ran like new. Bought a new sensor plugged it back in and its running great.

 

[ExPlOrErImPoRtS]

clean mass air flow

this is always my problem every year but I got k&N oil.

 

[not8taxi]

cleaned the maf still no good...wouldnt the CEL come up if it was a bad maf?

 

[clklotz]

I have the same problem. Very high idle. Replaced IAC, upper intake manifold, hoses, fuel filter, air filter, PVC, and mass air flow sensor. Someone told me to replace the EGR valve? Does that have anything to do with idling?

 

[not8taxi]

is your cel on?

 

[not8taxi]

today i went to the mechanic to try and find my idling/ stalling out issue...my CEL is not on...just to confirm that again...we looked for a while in the engine bay...he sprayed some stuff on it to detect air leaks but nothing...i decided to go ahead and replace the fuel filter...even though i did a few months back i just said lets do it again...so he did that...while under the car he was looking and located by the gas tank a piece that ties into the full system...i think it was a fuel canister...thats what he called it...he pulled it out and looked inside and told me that it was stuck in the open position...it also ties with another unit on the fuel tank that works together with it...he ordered the parts and im off tomorrow to get it replaced...ford even sent his a fax of the diagram...i will try and get it for everyone to show you guys...i hope this is my problem because i could not drive my car a block without it stalling out at every stop sign/light i come to...its really annoying me...will def write back to let you guys know how it goes


look at my chilton book and found the proper term...EVAP system....

Evaporative Emissions Control System...

 

[not8taxi]

UPDATE:

Well it took about 8 hours (waiting for ford to send parts...what a pain in the ass) but all is good and done...my mechanic replaced both valve cover gaskets because they were both leaking...replaced my pcv valve...replaced intake manifold gasket and also replaced the EVAP canister vent solenoid...and my car now does not stall out at the lights...im so glad the problem is solved...it was annoying...if anyone out there has the chiltons repair manual for the 02-03 explorer it explains it all on pages 6-24 and 6-25...