Lsquared

Hello...I have a 98 ES 300 with 105,000 miles and recently my car has been having a problem. When I start my car, the engine will start up but the idle will get lower and lower until the engine dies. If I start the car and give it some gas it will be ok.

I searched the forums and found out that I need to clean the IACV, which I did (thanks to detailed write ups ) but now the problem is when I start my car, the idle is real high. It idles at 2500 rpm and slowly rises to about 3000 rpm in about a minute or so. After about a minute, the idle will reach 2000 rpm and jump to 2500 rpm back and forth.

I have tried resetting the 15 EFI fuse, checking vacuum lines and hoses, unplugged the battery, and still no luck. I'm not sure what else to do. I don't think it's safe to drive the either. Any suggestions? TIA

92ES5sp

Is there a check engine light?

Lsquared

no check engine light

OceanView

I had the same problem after cleaning the IACV.
I drove the car around a few miles and the idle self adjusted.
try that and see if it works for you.

Lsquared

I just drove the car around the block and idle is still high (1700 rpm)...i don't even have to press the gas to move the car...i think it's a vacuum leak because i do hear some kind of hissing noise from the engine and when i put the car in park, the rpm fluctuates between 1600-2100 rpm

I think it might the IACV because when i pulled it apart from the throttle body, i notice there was kind of sticky gasket between them and the gasket didn't stay in one piece...half was on the throttle body and other half was on the IACV

That's the only place i can think of where the vacuum leak would be...Can i spray carb cleaner on the hoses? or should I buy some brake cleaner?

Your thoughts are appreciated...thanks!!!

llcoolpass

well duh, you need a new gasket, silly.
or use rtv
you must be sure to remove all the old gasket material before doing either, all while not scratching the surface.

OceanView

you need to replace the gasket with a new one as part of the cleaning process.

Lsquared

Well I bought some ultra black RTV and used it on the black coil and the IACV...rpm didn't jump anymore but high rpm was still there

So I figure wat the heck, I'll buy a new IACV and install it...now everything is working fine

I appreciate everyones help with my situation...thank you!!!