94 Bonneville idling @ 3000

[rgsmith68]

My daughters 94 Bonniville will sometimes idle up around 3000. Sometimes it will correct itself after a while, sometimes not. Usually after it has been doing this and then corrects itself, the check engine light will come on. Then if you turn the engine off and restart it, the light will be off again....please help! thanks
richard

[Hungrycat7]

Sounds like the throttle positioning sensor is sticking. It measures driver demand but like any part can wear out.

[maxwedge]

The idle air control could also be a probem with those symptoms. Make sure the throttle body or linkage is not binding also.

[rgsmith68]

Thanks guys! The rpm are also staying high going down the road. It will pull the car along at about 35 mph without touching the pedal. The rpm stay at a steady pace, not racing up and down. I also sprayed around all of the vacuum hoses, brake booster, and intake manifold (with carb cleaner) and did not discover any leaks. It does not seem as though the throttle linkage is binding up at all and it is returning down to the bottom of the idle position against the idle adjustment screw with no gap. So I guess I will start by replacing the throttle position sensor. I found one at autozone for about $60. I hope this fixes it. I will probaly change it out on Monday as I have to work all weekend. I'll let you know how it turns out.... Thanks again!