Hi guys,
I am trying to work all the small bugs out of my 89 GTA 5.7 before I pull the motor out to rebuild it. I bought this car off e-bay a few months back and have driven it about 100 yards. I bought it planning on engine-trans rebuild. I just changed the tan interrior which was trashed to black leather out of a 2000 trans. Carpet and trims are out of a 1990 formula. Anyway back to the engine.It has 113000 miles on it. It runs good if you keep your foot on the gas. It just won't idle. I plan on all new sensors with the engine rebuild.Should I screw around with this now or work on it once the new engine is in? Also one of my engine fans runs all the time even with a stone cold engine. What should I do?????

 

What engine was in the car originally? Was it a L98 also? Is your SES light on or hooked up?

The fan constantly on is often a sign of the engine being in "limp or safe" mode. GM generally turns on the fans for certain SES codes to avoid overheating since their may be a number of problems causing a particular SES code. Is it the driver's side or passenger side? If it is the driver's side, then the ECM is turning it on - probably for the reason I mention above. Passenger side could be cause due to a short as the passenger side is only controlled by the Fan Switch in the passenger side head.

If you are getting an SES code, then your idle could very well be affected too due to the ECM going into either "limp mode" or "safe mode". Conversely, if there is no SES codes, then you IAC may need adjusting.

Need more info.

 

I believe your coolant temp sensor is bad, or unplugged. I accidentally unplugged mine while the car was running and the fan came on. I shut it off, and when I tried to restart it, it would not idle at all. That sensor is located under the throttle body opening. It is the right side sensor, not the left one. It has a yellow and a black wire coming out of it.

 

I will check to see which fan it is. I believe it is the drivers side. I will also check the connections by the tune port mouth. The dash light does work and when I jump the plug it does not give any codes. Thanks

 

one thing i'd like to add..

the fans 'might' be grounded out, causing them to remain on..

sounds like a CTS problem, though