Check Engine Light On and Flickering

[Rare91]

Pulled the Buick out today to run some errands. Noticed after about a block the Check Engine Light was on. In the past if it came on I pulled over and shut car off and restarted and it went away. This time it didn't work. Finished running errands and came home and plugged in the laptop. Opened up Powerlogger and started the car. The light was on steady and flickering but no codes are listed. Shut down and restarted several times and keep getting the same results. Drove the car 3 weeks ago and did multiple road trips over the summer without any problems. Anyone have any advice, as I'm baffled why it is on, but not registering any codes.

 

[earlbrown]

I'd start with unplugging the ECM and looking for anything odd like moisture or corrosion or anything related to heat. Then CAREFULLY pop the chip out look at the pins (maybe CAREFULLY clean them with an eraser) and reseat it.