Totally strange. My '87 cutty 307 runs beautifully and has always done so (has 58,600 miles) but when I'm idling at a stop light, the yellow "service engine light" comes on. Once I start driving again after a little while, it goes off. Any idea as to why? Thanks, Michael

 

Pull the code to find out exactly what it is...
http://tlentz.oldsgmail.com/howto.html#Computer

Sounds like a TPS low error, which means the throttle position sensor needs adjustment or replacing.
http://tlentz.oldsgmail.com/howto.html#TPS
But pull the codes first to be sure.

 

THanks, Rob. I'll look into that. I see you're in Texas and I think I've read on your other posts that your in Dallas. I'm in Houston but have close family who live in Wylie, which is a subarb of Dallas just NE of it.

 

Yep, I know Wylie well. I drove through there last week when heading to Trinidad.