Cleaning the IAC and TB

[mi1dzyr]

How do you clean the IAC and TB? Out of nowhere my 1990 L98 started idling rough.

 

[Vettefan87]

The easiest way to clean the Throttle Body is to simply pull it off the plenum. It is only four bolts holding it onto the plenum other then the throttle linkage. After you get it off just use a rag and some carb cleaner and that will clean all of the grim and what not off. The IAC I am not sure how to clean. Hope this helps.

 

[mi1dzyr]

Thanks Vettefan,

the TB sounds easy enough.

Anyone else know how to cleanup the IAC as I think this is where these car inherit the rough idle from.

 

[wishuwerehere82]

Spray some carb cleaner on the pintle and spring and wipe it off with a lint free rag. Be careful not to get the carb cleaner down in the motor shaft, hold the pintle pointed down so the cleaner runs away from the motor.

 

[mi1dzyr]

Spray some carb cleaner on the pintle and spring and wipe it off with a lint free rag. Be careful not to get the carb cleaner down in the motor shaft, hold the pintle pointed down so the cleaner runs away from the motor.

Thanks Pete, does the IAC have to come off to clean in order to no get the cleaner into the motor shaft?

 

[wishuwerehere82]

Yes, it will have to be removed to get to the control valve surface. You may want to get a new gasket for it before you remove it.

 

[Ken]

Our good friend in the Corvette Community, Lars Grimsrud, has compiled a nice set of instructions for removal, cleaning and reinstalling and adjusting the TPS and IAC. You can read his information here: Maintenance: Throttle Body Cleaning.

Lars has proven himself to be a valuable asset to the Corvette community.

 

[vette-dude]

Don't use Standard Carb Cleaner. Use Throttle Body Cleaner!!!!! I use a old toothbrush to scrub the inside of the throttle body. Make sure the hole that lets air into the IAC is unobstructed also. Should be just in front of the throttle blades.

Randy

 

[mi1dzyr]

Our good friend in the Corvette Community, Lars Grimsrud, has compiled a nice set of instructions for removal, cleaning and reinstalling and adjusting the TPS and IAC. You can read his information here: Maintenance: Throttle Body Cleaning.

Lars has proven himself to be a valuable asset to the Corvette community.

Thank you Ken for pointing me to Lars' compilation of the IAC TB cleaning instructions. I would have to agree with your statement of Lars, I once had him on my cell phone while he walked me through my first work ever on my C4, replacing my altenator...he's a valuable friend to the Corvette community.