What does it mean and where is it coming from? The rpm gauges rev up and down from 1 grand to a little over the 2 grand mark. So somebody please let me know what this is. Thanks.

 

If it's just cold when it does that, It's more then likely the IACV. (idle air control valve) but if it does it constantly, it could be the FITV, or you can have a bubble in the coolant system, which usually it should take its self away if it's a self adjusting coolant system. Any more symptom's, when cold, when hot, etc etc?

 

or it could be tps sensor, mine did that.

 

Could be a vaccum leak as well

 

This is the easiest thing to check for, so I'd look this route, first.

If you find a hole anywhere on the intake side of your engine, put your thumb on it. If it is sucking air, and you put your thumb on it and it changes the way the engien is acting, you found your problem.

BTW, there is a tech section here for car problems, so this is the wrong forum.

 

yup move to tech talk.

 

A good way to check for leaks is to spray carb cleaners around the lines (spray some around where the intake manifold connects to the head for good measure as well) and see if the idle changes at all.

 

What kind of car do you have? If its a honda, with alot of them, its the Idle Air Control valve. Thats only if it does it once warmed up, if it does it when its cold, its your Fast Idle Thermo Valve. These are common occurences. In my case, it was my Idle adjust screw. Needed to be turned abotu another 1/8th of a turn.

I have some extra working FITV's and IACV's if you want to troubleshoot. Just let me know what kind of engine you have. Its a simple replace.

 

yea i just had that problem with my 2000 lude after doing the coolant bypass mod on the tb...

it was fluctuating between 1000-1500 rpm when warm and after tightening the iacv screw or whatever it is, its stayin steady at 750... its not that hard to do either

 

Yea I appreciate it man. If can give me a call at 515-1773 my name is Mark and I have a Integra 95. Thanks.