I have a 95 z28 i just recently added AFR heads a custom grind cam550/550 lift 112 lsa. Today I was going to go dyno the car. When i started it everything seemed normally. I was standing outside of the car smoking (I do not smoke in the car) letting it warm up and I heard the fans turn on so I got in the car and the check engine light was on. I know that I need to get the car scanned and my buddy is coming over tomorrow to do it I was just wondering if anyone has heard of something like this before?

 

My car does the same thing- fans come on, check engine light comes on. The fans also seem to come on at times when the car isnt fully warmed up....however the car only does this periodically. Im getting my car scanned soon....let me know what your codes come up as- probably the same issue. I have heard this could be the A\C Temp. Sensor, which causes the car to think the air is on, which causes the fans to activate when they shouldnt. Let us know what you find out....

 

My car does the same thing as well haha, let us know! I think it could be a lot of things though because if a sensor is giving bad data the computer can start ignoring it and going into open-loop mode, so the fans turn on. Nonetheless, let us know what you find out! My bets are on an O2 sensor!

 

Interesting...Well I guess we both will hopefully both learn something here 95slvrz28!

 

When certain trouble codes are set, the PCM turns on the fans to protect the engine. They are supposed to act that way. When the check engine lite goes on, the PCM has to be scanned to see what the complaint is. It is cheaper to scan than to throw parts at the engine for no good reason.

 

Any news on what the problem turned out to be?