Idleing problems

Could be alot of things.

First thing would be to check the codes. Do a search to find the method....its very easy to do (jumper the test connectors with a paper clip...count check engine light flashes).

Second.....a COMPLETE tuneup. New....;
- plugs
- cap
- rotor
- plugwires
- fuel filter
- clean MAF meter with electronic cleaner
- clean throttle body and idle air bypass valve with intake cleaner
- check timing
- check all vacuum hoses for leaks
- check fuel pressure
You can do each of these items, one at a time to see if it makes a difference, but if you havn't done a tuneup on the car before, all of the above should be completed (you'll be amazed at the difference).

Third, if you're still having idle problems and have completed the tuneup and resolved any codes that the computer throws, you may have to look at the sensor's. A sensor can be bad and still not cause a check engine light.
The sensors that WILL ABSOLUTELY cause an idle problem if they are bad are the Air Charge Temp sensor (ACT) and the Engine Coolant Temp (ECT) sensor.

Fourth, if you're still having idle problems, you might have to adjust the idle set screw.......I would definately complete all of the above items before I did this though. (didn't have to do this on my car)

Assuming that you're car just has normally wear and tear (no major mechanical problems), completing the above steps should settle your idle down. I've completed all of the above steps on my 95 GT over the past year, and my car idles rock steady at 700 RPM and feels real strong for a stocker when driving. (It idled/drove like $h!t when I first bought it last summer)

Hope that helps.

Everything that silver85tc is right, but I just want to add something that I did that fixed my idle somewhat.

It didn't totally fix the surging problem, but it fixed most of my problem, but I replaced the PCV valve. I get better gas mileage also.