1987 Iroc-Z 5.7 TPI, hypertech chip, 160' thermostat, fan switch, shift kit, 3.72 gears, and Borla. The car has been running great for days now. I shut off the car the other evening and went in my house for dinner. Came out about 1 hour later and started it up. The car surged at idle, started at 800rpm and slowly went down to 300-400rpm and eventually stalling. I took it to a local repair shop and they checked for codes. We replaced the MAF and it still did it. They said it was thowing a code every 20-25 starts but I don't remember what code number. No check engine light stays on. They checked the fuel pressure, idle, ECM, IAC sensor, MAF. They have no idea whats wrong with it. It was even acting up while they had it. The TPS harness clip is broken. It was that way when I bought the car. I wrapped it with electrical tape so it would come off. Could that be the problem? I am lost here! And my secondary fan won't kick on either.

 

99,

Did anyone test the CTS? Replace the TPS connector, since you know there is a potential problem with it, but test the CTS at a known coolant temperature.

 

Please excuse my ignorance but what is a CTS and how do we test it?

 

Coolant Temp sensor, You Ohms check it at a known temp, let it sit and check the ambiant temp then ohms check the sensor (usually on the front of the intake manifold or right hand head) If you post the temp and ohms reading, I'm sure someone here will be able to tell you if it is good or bad.

~M~