I have a Topaz ( Tempo ) with a 2300 4-cylinder engine. I have replaced the TPS ( Throttle Positioning sensor ), cleaned the throttle body as best as I could without tearing it apart but it is still racing. I have noticed that when it is idling (fast) that the rpm is increasing and decreasing without anybody touching the throttle. Any Suggestions?
"fgellis" wrote in news: snipped-for-privacy@localhost.talkaboutautos.com:
That is the ISC trying to get rpm down.
Does this happen immediately when you start the car?
Engine warm or cold?
Disconnect the vacuum line at the manifold, the one that feeds accessories, plug that port. Does it still happen.
It does happen almost immediately after we start the car, although it does seem to speed u a little more as the engine gets warmer.
The 2300 engine in this car is fuel-injected, so I've been told it doesn't have an ISC. Could it be the Idle Air Control Valve or Air Charge Temperature Sensor ?
"fgellis" wrote in news: snipped-for-privacy@localhost.talkaboutautos.com:
Terms keep changing.. they IAC, IdleAirByPass (IABP) ISC, (except Air Charge Temperature Sensor - which is part of the MAF)
all do the same function.
Look for the vacuum leaks, like I said, also check for intact PCV Valve
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