I am having a problem in that my idle surges from 200 rpm to about 2000 rpm when first started. It seems to correct itself once operating temperature is reached. As stated in subject line it is a 91 Laser 2.0L non turbo 5 speed. I have replaced the TPS as it was dead, but there is little improvement. Any suggestions group??

 

Isn't it normal for it to do that if its an EFI system as when you start the engine when its cold it would reach around 2000 rpm acting like a choke so the engine won't stall requiring a ritch mixture of fuel untill the engine warms.

 

Hi. Thanks for the response. It would be normal if the revs stayed high (like a choke) but as I stated the idle surges up and down continuously until the engine reaches operating temperature. I am wondering if the idle speed control servo controls this. Any suggestions?

 

I have a 93 Eclipse and it would idle up and down ,probably 300 to 4oo rpms while idleing ,and they replaced the idle air control valve to fix it but other than that the car ran fine but if you would give it gas the throtle would stay high and slowly go back down to the eratic idle . you would never know somthing was wrong driving down the highway.

 

I had this problem on my eclipse. There's a sensor right below the intake piping on the intake manifold, I believe it's right before the throttle body. It's attached by two small bolts. Take it off. The sensor can be taken apart to be cleaned and most off the time it's not too late for the sensor. There are three screws you need to take out to take apart the sensor. Clean the inside of the sensor with carb cleaner. That's right, carb cleaner, not throttle body cleaner. For some reason it works better to clean the sensor than throttlebody cleaner. I even shot some silicone inside to keep the parts sliding nice inside. Put everything together, plug the sensor in and you should be ok. I was told if you let the car's idle surge like that, you risk blowing out the ECU.