ppg97ek

Hey guys got a slight problem my idle is bouncing from 1000-2000 I think it has something to do with my IAC, but my question is there any way of possible adjusting that or do I need 2 replace the IAC completly

RC000E

It's unlikely its the Idle Air....that's the f*ckin annoying H-T answer to all idle problems that is rarely the actual issue. What is FAR more commonly the issue is the thermo valve below the throttle body. The valve seat inside screws it's way out and the valve never seats when the motor reaches operating temp allowing constant blow by air...essentially a vacuum leak.

Pull off your intake tube and idle the motor to operating temp. On the inside of the bore of the throttle body there are two holes in the side. With the motor at operating temp put your finger over the lower hole. If it's sucking vacuum at operating temp, that's a problem. You need to take the assembly apart beneath the throttle body, screw the plastic valve seat all the way in, then back it out 2.5 turns. You don't want the valve seated when cold, but as the coolant warms the thermo valve you want it to seat and shut off the bypass air.

That's likely your issue. Check that first, then if that isn't it check the idle air. The Idle Air gets blamed on this site constantly for bad idle just simply because the work "idle" is part of its name I swear. I've done this for years and I've fixed the bouncing idle syndrome more times than I can remember and out of all the times the IAC was bad twice, maybe three times. When they are bad the rubber boot inside is usually cracked or broken down. The IAC's are pretty straightforward to check. Get a two pin plug as a test plug and run some extension wires. Hit the IAC with 12v....if it clicks it's good. It's a simple solenoid...that's why they rarely go bad.

ShortyzKustomz

When does the idle problem start? Mine is doing that now and it IS the IACV, When I start mine up in the morning it idles at like 3200 rpm for about 30 seconds that starts jumping, And every other time I start it during the day it goes to jumping. I blocked off airflow to the IACV inside the throttle body and it idles perfect.

garyc17

I have a ITR intake manifold and ITR throttle body. There is no thermo valve. Would it be the IACV in this instance? My mech tells me its tune related and to sort it out with my tuner.

solsi

My idle was bouncing because i had air in my coolant system and a great loss of coolant due to a leaky rad.
Replaced witha mishimoto rad and bled my system and now its fine. I had cleaned my iacv also and it helped a bit but the iavc was not the problem in my case. The air just threw off the iacv because it wasnt getting coolant

ShortyzKustomz

Yeah coolant can be a problem too, mine was bled and was the iacv though, Not sure about the itr setup, could be a tuning issue

ppg97ek

So your saying to if I feel it sucking that is the problem!!!

ppg97ek

I tried what you told me and it was sucking air within the TB, then I adjusted the screw like you said and I also tried it like the car manuel says but I still have the idle bouncing. Could it possibly be that considering I put on a new intake manifold, got it bored to match the 70mm TB I am going to put on once I get the TPS might affect why it might still bounce and thAT SUCTION IS COMING FROM WITHIN the TB???