loligator

Hey all,

My girlfriend has a 98 Chevrolet Cavalier Z24 (2.4L). It started running real rough, idling very funny (the idle was all over the place, up and down, up and down), and then the check engine light finally came on. The code I got from it said the throttle positioning sensor had a low voltage reading. I've since replaced it and the idle isn't all over the place but it's not right either. Lets say I'm driving 55 down the highway and I'm coming up to a red light. Hit the brakes and the idle goes down as expected, but probably 9 times out of 10, it will stay at 1500 for about 10 seconds before dropping to where it's suppose to be. The OBD II scanner I have also now picks up a high idle code.

I followed the repair manual when I installed the sensor. They warn that improperly installing it could result in a high idle or other idling issues. The instructions said to slide the sensor onto the shaft, then rotate it counter clockwise until the bolt holes are properly aligned. I didn't have to turn the sensor at all... It was properly aligned when I slid it on the shaft. Should I have spun it 360 degrees counter clockwise? The instructions don't say to do this and there isn't really enough clearance to do so anyway. I even removed the sensor and reseated it thinking maybe I did something wrong but still the same result.

Although the car is drivable, I'd still like to get this resolved. Any ideas would be greatly appreciated.