I rebuilt my LT1 with heads, cam and supporting parts. I bought a PCM from a 94 to run in my 97 SS swapped it in and added a tune.

But I notice the "Check Gauges" light flash very rapidly at times. All gauges are reading like they should. What could be causing this?

 

On a '94 check gauges illuminates for alternator voltage high or low, oil pressure low, or coolant hot. The circuitry is all internal to the dash cluster, nothing to do with the PCM. However I do not have schematics for a '97 so I can't help.. Maybe someone else could chime in..

 

Normally, the flashing SES means a misfire.

 

Yes, but this is check gauges light, not service engine soon light.

 

Geeze, for some reason I missed the "Check Gauges" part.

 

Just a thought... Since the gauge dials are buffered to move smoothly maybe you have a loose or dirty connection on the oil sensor or temp sensor (on left head) that is bouncing the signal but not long enough to move the gauge. If it was an alternator connection/problem you would probably see lights dim/brighten.

 

I did, too, the first time I read it. I have never heard of the check gauges light flashing.

 

Yes, it is a weird one. It is annoying, might just pull the bulb because I watch my gauges religiously and do not need a light to tell me to look at them, but I would rather fix it right.