idle air control valve trouble!!! please help!!

[98ranger4x4]

i have been having trouble with my idle air control valve, the engine was revving up on its a while ago so i pulled the iacv off cleaned it lubed it and put it back on but lately it has been doing the same thing but now every time i clean and lube it it only lasts for a day or two and then starts revving up again (it only does it when the truck is moving). any suggetsions??

 

[Earl43P]

Buy a new one or make an IAC gasket with a smaller hole (bandaid) until you can afford a new one.

 

[98ranger4x4]

any idea how much a new one would cost?

 

[Psychopete]

any idea how much a new one would cost?

Look around, Rock Auto has some cheap ones, but typically you get what you pay for. I think I paid $70 for the one on my 2.9L..

Pete

 

[bikerboy]

Here you go. I put in a 89123 zip code for Nevada. Duralast are usually a good brand for stuff. And it comes with a two year warranty.

 

[98ranger4x4]

thanks for the help guys, but unfortunately i need some more alright, so i replaced the iacv yeterday and today it started to do the same thing, when i am moving and push the clutch in it will rev up to about 3k, it only does it sometimes and as soon as the truck comes to a stop the rpms drop back to normal. so now i dont know what to think, every time i would clean the iacv before it would stop but now it has a new one and is doing the same thing. any ideas?? thanks again!

 

[betomonroy]

by any chance have you installed an AIT sensor module?

 

[98ranger4x4]

by any chance have you installed an AIT sensor module?

i dont even know what that is lol. could the gasket possibly be the problem? the new iacv didnt come with a new gasket.

 

[betomonroy]

I have a similar problem and it just started today.The only difference is that I have an erratic Idle speed that it doesn't goes to 3K RPM. We'll see what happens...

 

[Supermini]

This must be a pretty common problem... Mine began doing this exact same thing a week ago and I haven't gotten to the bottom of it yet but here is some info that will help explain it partially. The ECU takes info from your ABS/Speedometer sensor on your back axle. When it senses that the vehicle is moving it raises your idle a couple hundred RPMs so that the RPMs don't drop as fast in between shifts and makes it much easier to drive. I am having the same problem and I just replaced the idle air control with no difference. I am leaning towards maybe the throttle position sensor not sensing that the throttle is closing all the way and telling the IAC to do goofy things or possibly the crank or cam sensors not sensing the correct RPMs (that's a weak theory but I have an aftermarket tach so I can't tell ya what a stock tach would be doing if it was working off the faulty sensors?) Hope someone speaks up with a good fix...

 

[98ranger4x4]

just an update, i discovered that there is a vent hose coming from right below the oil filler cap into the intake tube that soemhow got disconnected (letting air in past the MAF) which is very bad because there was dirt in the intake and throttle body. i pulled the throttle body off and cleaned everything and drove it and it isnt revving up like it was but it still doesnt quite seem right, but much better. i am hoping maybe everything just neeeds some time to reset and it will go back to normal.

 

[MUDDING B-3000]

my truck did the same thing an my mechainc changed the idle ari control valve an it worked for about a week then it doin the same thing until it warms up then it will settle down to 700 800 rpm but when i drive then come to a stop the rpm will stay up at like 2000

 

[Bryan22]

i don't know if you guys got this figured out, but im pretty sure that's normal. it stays at a higher idle speed when you're rolling so the engine dosen't die. then when you're stopped it idles back down to the normal 700-800 rpm.