'92 lesabre check engine light randomly appears

my service engine light comes on and off randomly and stays on anywhere from a few seconds to a minute or so. There doesn't seem to be a pattern. Cold, warm, short distance, long distance....doesn't matter. Can't test codes because light is never on when started. Any suggestions? Thx

You should download those codes anyway. The reason is that even though the light is off, those codes are retained in the computer for a number of ignition cycles and will display when outputting them. I've seen bad Oxygen sensors cause this on-off type of light and I've also seen this behavior in a retry failure sceneo where the cooling fans couldn't be started due to a bad relay. Why guess, download the codes to find out the cause.

Local Autozones can do this for you for free, or you can do it yourself by jumping two pinouts in a connector located under your radio/ash tray.

The following link tells how to pull the computer codes off GM vehicles (80-95):

http://www.geocities.com/dann8785/serviceenginesoon.html