erratic "service engine soon" light

[gmhowe]

turned the key on the beast today and the "service engine soon" light started flashing very fast and not very bright. Car started but then after 5 sec quit. tried again and same thing. could the ECM have gone bad ?

 

[gmhowe]

ok full story, I had installed one of those hypertech chips long before I found this site and reading the article in the Corevette Fever mag, that I posed a thread on recently. so I disc the battery and took out the ECM and put my old chip back in. reinstalled the ecm and reconnected the battery and thats when the 90 mile an hour "service engine soon" light started. I took out my orig prom and put the hypertech chip back in and the car runs fine ??? I would like to use the orig chip but the car won't run with it in. Perplexed .

 

[89vert]

Seems to me I read some where that if the SES light flashes it is because the PROM is not inserted properly. Wish I could remember where I read this. Hope this helps. Tim