Question: Code 15

[PokerJoker]

Took my 81 out for a ride today. No check engine light since replacing the ECM (about 6 months ago), everything's been fine. About a minute into the ride the CEL comes on but for only about 30 seconds and then goes off. Ride around about 20 miles and then back home. CEL never comes back on. Check for thrown codes and code 15 blinks.

Question is...if the light goes back off on its own, has the problem resolved itself? Do I need to be concerned about this?

Thanks,

Jeff

 

[gmjunkie]

Took my 81 out for a ride today. No check engine light since replacing the ECM (about 6 months ago), everything's been fine. About a minute into the ride the CEL comes on but for only about 30 seconds and then goes off. Ride around about 20 miles and then back home. CEL never comes back on. Check for thrown codes and code 15 blinks.

Question is...if the light goes back off on its own, has the problem resolved itself? Do I need to be concerned about this?

Thanks,

Jeff

Check the connection on the temp sensor,you may have a loose,crudded up plug,or the sensor may be going out of range!

 

[PokerJoker]

Check the connection on the temp sensor,you may have a loose,crudded up plug,or the sensor may be going out of range!

Thanks gmjunkie, I'll check it. This would be the temp sensor up on top of the intake rather than the one on the drivers side of the block, correct?

 

[Tommy Almond]

Shouldn't be a problem, but letting you know what may be needed soon

My old school corvette mechanic told me if the Check Engine light comes on and goes off usually not a problem, only if it comes on and stays. Intermitting light could be just an off reading caused by loose connections, sensor going bad etc so could be an alert to a future problem but the temp sensor is easy to swap out.
Even after swaping out many of my sensors and 99.9% of the time my system runs fine and normal, every once in a while right after cranking cold start and left at high idle I may get a Check Engine light on for about 10-15 seconds and its the 21 code or O2 sensor but that has been changed so assume it may be a little rich right then, but gas it some, light is off and she runs fine from there on.
Beauty of it all is that you still have the system intact and working as factory designed it and the system can alert you to problems before they really become a problem.