Idle is High

[Ky1845mechanic]

95 Saturn SL2.It has a high idle about 2000 rpm".It will come down but then sometimes will go back up.I have checked the engine for vacuum leaks and it is pulling a steady 19 inches.It has refused to start before after shutting down.Real strong smell of gas.After a coupla hours it started right back up and ran fine.We had another engine that was blown up and saved the sensors on it and I have replaced most of them on this already.New fuel pump and filter,plugs,wires and about the only sensor not replaced is the one in the air cleaner snorkel and the oxygen sensor.Have cleaned the egr valve and also the throttle body.

[alfieferenzo84]

clean your egr valve!

[yaz4real]

Sounds like the classic symptoms of the ECTS.. engine coolant temperature sensor ( $11-$18 ) found on the drivers side cylinder head. It has two wires going to it. It takes a 13 mm deep socket to remove it. If you've never changed it before and if its original, it is resin tipped and go bad. You will see when you remove it. The replacement is brass tipped.

There is another sensor nearby and in front of it with one wire. That is for your temperature gauge.

It takes a little finesse to remove the connector. If the connector has green corrosion on it, it will need replacement also. It is more expensive than the sensor. ( $22 - $28 ) Doesn't matter how its spliced in.

Do the sensor swap on a cool engine. Put a rag below the sensor. About three ounces of coolant will come out with the exchange. You'll see a difference immediately.

If the above has been done before, look at the idle air control valve. The best way to ensure it is clean and operating is remove the throttle body, ( 2- 10 mm bolts ).. disconnect the TPS and IAC and remove the accelerator cable... its a great opportunity for a thorough cleaning.. do not soak the IAC just clean... buy a gasket ( $ 2)