Question: Service Engine Soon

[blmann]

About a minute after I start the engine cold (1993 LT-1), the engine light comes on and both the primary and secondary fans come on. The fans stay on until I shut the engine off. If it is a warm day and the motor is up to operating temperature, if I restart engine the light and fans do not come back on. Must be some sensor?? Any ideas?? Bob

 

[toptechx6]

About a minute after I start the engine cold (1993 LT-1), the engine light comes on and both the primary and secondary fans come on. The fans stay on until I shut the engine off. If it is a warm day and the motor is up to operating temperature, if I restart engine the light and fans do not come back on. Must be some sensor?? Any ideas?? Bob

The SES light indicates there is a fault code in the ECM, the fan runs by default when many codes are set. See the link to learn how to pull the codes using a paperclip. For best results troubleshoot the code using the correct factory service manual.
The codes do NOT indicate a part is bad, only that voltage in the circuit is out of range, codes can be caused by shorted wires, poor connections and even mechanical failure.

Recovering the C4 ECM Codes - www.c4vettes.com

 

[vetteboy86]

As mentioned in the previous post, and just to reaffirm pulling the codes is really the first place to start.

There are several guys that have ECM expereince with your model, and there sure to chime in soon.

By the way, Welcome to