86StillRunning

My '86 4000s "check engine" light comes on several minutes after I start and run the car. Car is running very smoothly (for its age). Several mechanics I have had have said it is just engine wear, and I assume they are suggesting it is due to an anti-knock sensor? I know there is also an O2 sensor that will cause the light to flash, from a search of the forums. Are there any other inputs?

I have to go to the dreaded emissions testing here in Maryland, and they will not accept warning lights being on. Any suggestions other than the obvious one, i.e. pull it out?

I have read about changing the timing if NOx emissions are excessive, and some of the fixes to be done to clean things up, tune-up, O2 sensor, make sure it is warm, etc. Any other ideas appreciated.

Thanks.

Lara