I've had this problem for a few weeks now. My car usually idles around 500rpms and a little rough with the cam I put in. But now the car idles and surges anywhere from 400-1000 rpms and seems to be worse once the car is warmed up. Also when driving the car hesitates up to about 2000rpms. I brought it to a couple mechanics and they said its probably a bad plug or wire. So I had the plugs changed, new MSD wires and coil, cap, rotor and Accel ignition module. The problem is still there. The car sometimes stalls when I'm stopped or it stalls when it is idling and i turn on the heat or A/C. I did find one vaccum leak and I replaced the vaccum line but that didn't help anything. The car also has a new MAF sensor. To top off everything I get my car back from getting the new plugs installed now my fans don't work. I have a wire spliced off the sensor to a switch so I can control them manually. I checked all the wires and they were good and the fuses were also good and I changed the relay and the still don't work. Please help.

 

My Honda and Camaro do what I imagine, is a simliar idling problem. I haven't found the answer to it yet, unfortunately.

As to your fan situation, replace the senser/sender unit. I had the same problem (as do many other Thirdgen Camaro's), and the plastic lining around mine was fried.

 

89,

Are there any error codes? Even if the SES laight is not on, you should scan.

To isolate the fan problem, ground the dark green/white wire at the fan relay. If the fan operates, the circuit from the relay onward is O.K., and you have a control issue. The ECM operates the fan relay based on CTS input, so I'd check there first. The CTS also has a huge influence on mixture control, so it would be even more important to verify its operation. You can check it with an ohmmeter:

 

i had that problem so all it was for me was new plugs and wires, now i can get to higher rpms. hope this helps