: Thottle Body



akaz87
02-18-04, 12:43 PM
I have been told I need to clean my throttle body in order to fix my slightly rough idle. How can I do this? What do I need to clean. 1998 STS

Aurora By Olds
02-19-04, 12:24 AM
Take the plastic tube off of the throttle body, get a rag or two, some carb cleaner, and clean out everything thats dirty inside the TB. It helps to have someone else handy to hold the throttle at WOT while you clean the back of the throttle plate and further inside of it.
Once its squeaky clean in there, your idle should improve.

akaz87
02-19-04, 12:25 AM
Take the plastic tube off of the throttle body, get a rag or two, some carb cleaner, and clean out everything thats dirty inside the TB. It helps to have someone else handy to hold the throttle at WOT while you clean the back of the throttle plate and further inside of it.
Once its squeaky clean in there, your idle should improve.
Hey THanks a lot,
I'll try to ask someones where its located. Not exactly sure of this stuff. Thanks a lot though

growe3
02-19-04, 11:05 AM
See attachment for Throttle Body location.

-George

akaz87
02-19-04, 11:25 AM
Wow hey thanks a lot for the picture. Thats a mayjor help! So I can just pull all those tubs off and just start cleaning I guess them huh? Thanks again!

BeelzeBob
02-19-04, 01:39 PM
I have been told I need to clean my throttle body in order to fix my slightly rough idle. How can I do this? What do I need to clean. 1998 STS

Cleaning the throttle body is recommended as a maintenance item to allow the idle air control to control the idle speed as required and to eliminate any "stickyness" the throttle might have when driving away from idle....but....cleaning the throttle body will have no impact on a rough idle. If the engine is missing or idling rough that would be another problem. The throttle body just meters the air flow into the engine. If it gets dirty then the engine might stall or surge due to the idle air control "loosing" control of the idle but it will NOT affect the idle quality...the roughness that you talk about.

If the idle is not smooth then I would start to suspect the usual players like spark plugs, spark plug wires, injectors, fuel pressure regulator, etc... Instead of just randomly replacing parts until the problem is found get the car to a reputable dealer or diagnostic shop and have them put it on a scope so that they can pinpoint which cylinder is misfiring or causing the rough idle.

Your 98 has very extensive onboard diagnostic system that can often pinpoint the problem for you. Have you checked for diagnostic codes and/or is the check engine light on??

I would doubt that you have a cylinder "misfire" as there is a very strict misfire diagnostic code that will detect cylinder misfire and set a diagnostic code. The diagnostics for the mis-fire detect are very robust and can be depended on to notify you of a cylinder misfiring. If you don't have a check engine light then there is no misfire and no reason to start changing parts.

Are you sure the idle is "rough" or is it the characteristic slightly "lumpy" idle of the 300 HP L37 engine in the 98 STS??

akaz87
02-19-04, 01:43 PM
Cleaning the throttle body is recommended as a maintenance item to allow the idle air control to control the idle speed as required and to eliminate any "stickyness" the throttle might have when driving away from idle....but....cleaning the throttle body will have no impact on a rough idle. If the engine is missing or idling rough that would be another problem. The throttle body just meters the air flow into the engine. If it gets dirty then the engine might stall or surge due to the idle air control "loosing" control of the idle but it will NOT affect the idle quality...the roughness that you talk about.

If the idle is not smooth then I would start to suspect the usual players like spark plugs, spark plug wires, injectors, fuel pressure regulator, etc... Instead of just randomly replacing parts until the problem is found get the car to a reputable dealer or diagnostic shop and have them put it on a scope so that they can pinpoint which cylinder is misfiring or causing the rough idle.

Your 98 has very extensive onboard diagnostic system that can often pinpoint the problem for you. Have you checked for diagnostic codes and/or is the check engine light on??

I would doubt that you have a cylinder "misfire" as there is a very strict misfire diagnostic code that will detect cylinder misfire and set a diagnostic code. The diagnostics for the mis-fire detect are very robust and can be depended on to notify you of a cylinder misfiring. If you don't have a check engine light then there is no misfire and no reason to start changing parts.

Are you sure the idle is "rough" or is it the characteristic slightly "lumpy" idle of the 300 HP L37 engine in the 98 STS??I have replaced all those elements except the injectors. I have taken them all appart and cleaned them. I dont know how to check the Onboard Diagn system. The Engin Light isnt on anyhoww. Thanks

BeelzeBob
02-19-04, 01:52 PM
Simultaneously press and hold the OFF and WARMER buttons on the climate control with the key on and the onboard diagnostics should activate. Codes will be displayed on the DIC.

akaz87
02-19-04, 01:54 PM
Its a 98, The warmer colder button is a dial with the on and off . Its like a button that u can push for on and off and turn for colder warmer.