Hi,
I have a 1994 Audi 90 CS Quattro, it has about 230K km and I've had it since October. 5 speed.
Yesterday, I was driving home and the check engine light came one. Solid.
I pulled over, shut it down, restarted, no light.
This morning, same thing. Check engine light came on about 15 minutes from home (cruising at about 105km/h).
Shut it down, no light. But the light came back on after about 5 minutes.
Sounds normal, small amount of surging when idling, but that's to be picky.

I took it to the garage, but it's pre-universal computer hook ups so my mechanic couldn't check the code. The nearest European Auto mechanic is about 100 km away.

The car was low on oil, and is due for an oil change.

I topped it up, and took it for a drive, but again, 15 minutes later, the light came back on.

This has never happened before. The car is running at normal temperature.

I want to get it scanned, but the mechanic I have to take it to is only open the hours I work, so I can't get in there right away.

Any ideas?