98 Chevy 4.3 TBI

[mommicked]

Any GM techs around?? What does the bulb shaped sensor in the throttlebody do? I had to replace my throttlebody w a junkyard one In good shape, I cleaned the bore well w brake cleaner but did'nt clean or mess w the sensor though and used a new tb gasket/o-ring. It seems fuel mileage may have dropped a little w the new, identicle appearing 99 TB. should I try installing my old sensor?

 

[BlkY2k]

Re: 98 Chevy 4.3 TBI

TPS ? Throttle position sensor ?

 

[BlkY2k]

Re: 98 Chevy 4.3 TBI

If so they can be diagnosed and adjusted.
http://easyautodiagnostics.com/gm_tps_test/pickup_van_tps_1.php

 

[mommicked]

Re: 98 Chevy 4.3 TBI

No, the other sensor, It is in the small passage that passes air into the intake, when the butterfly is shut at idle.

 

[BlkY2k]

Re: 98 Chevy 4.3 TBI

IAC idle air control, they can become carboned up on the end of the pintle and can be cleaned with throttle body cleaner. They will normally cause a erratic idle though when they act up, or will hang and cause a slow return to idle.