My car has a dirty stock 48mm TB. The car will run smooth somtimes and real rough at other times, it only runs rough at idle or when it's in gear and I'm sitting at a red light. I also have to hold my foot on the gas and brake when I race because otherwise the car bogs and has terrible throttle response. Otherwise the car runs perfect, I can floor it at any speed and it just roars. Could this have somthing to do with a gunked up TB?

 

Probably the IAC is gunked up. Go to the tech section, there are procedures for removal, cleaning etc.

 

Dude, I had a poor idle even after fixing about 5 things that were wrong and throwing codes. It wasn't really rough, but it just wasn't right either. After cleaning the TB just what we could reach fixed the problem. Even a small about of that black film was causing problems. Actually my mechanic told me that it could cause idle problems and sure enough, after he cleaned it, problem solved. I doubted that it would actually do anything, but it did. Like I said, he didn't clean much, just what he could reach with his finger and a cloth.

 

iceman02

So you left the TB on the car and just stuck your finger in there and cleaned it that way?

 

I usually use an old toothbrush and carb cleaner to get it clean. Try this before you remove the throttle body and hopefully that's all you will need to do.

 

Yea, just left it on, opened up and cleaned with a rag and solvent. Didnt't think it would help, but it did... I guess it helps the air get in during idle around those butterfly valves.

 

I went and got some carb cleaner today and cleaned the TB. I left it on the car and sprayed the carb cleaner into the open TB and scrubbed it with an old tooth brush. After I was done the car idles like it's brand-new, it was idling like I had a wild cam before and now it's perfect. Thanks for all your help guys.

 

Odd how such a small amount of buildup and easy fix can make such a difference, huh.

 

ya, I'm very happy that this solved the problem, I thought it might have been somthing more serious.