Rep Power: 0

I have a -89 GL with fuel injection that has just begun to lit the CEL. It seems to light up when the engine gets some load. F.ex. when driving uphills or when exeeding about 80km/h on a level road.

The LED on the ECU just shows short regular flashes all the time even when the CEL is lit. No error codes to give me a hint of what might be wrong.

The car has just been in for it's yearly inspection and the exhaust readings was good with lambda 1.00 and CO at 0.0%.

There are no other signs of any problems. The engine appears to run perfectly and has a stable idle.

The car has about 147000 km on the odometer. The middle section of the exhaust pipe has just been replaced, the old one had large holes letting out almost all of the exhausts that way...

Any help to trace down the problem will be greatly appreciated.

 
Rep Power: 292

You sure your gas cap is on tight?

 
Rep Power: 0

Yes, and the sound when opened tells me there is pressure.

But why are there no error codes when the CEL comes on? Are there some jumper that has to be set or other trix they use to obscure the codes?

What is the next step to find the problem?