CEL Check engine light

[M100TURBOFR]

Hi. Lately (but not systematically) my check engine light comes on and stays on. If I stop the car and restart, it usually does not come back on again (till the next time).
Any clues to what is causing this? Thanks.
David

[HJ2]

Do a search for ‘paperclip test’ or ‘cheapscan’. Follow the procedure and post the result here.

[Tuga2112]

the engine management manual has a section for intermittent CEL codes as well. you can follow the flow diagrams to diagnose issues..

although you gotta keep in mind those flow diagrams were written by people with theoretical knowledge of the car and not practical experience (they were written before the car was on sale)

[M100TURBOFR]

Hi again
Paper clip test showed apparently code 42 (Electronic Spark Timing (EST) circuit). Otherwise car running fine but CEL light continues to light up intermittently.. Did notice however that the ALDL connector terminals were a bit "greenish" due to condensation no doubt. I'll have to buy some terminal cleaner spray and clean them up.
Thanks HJ2 and Joao. Anything worth worrying about?

[Tuga2112]

did you read the manual ?

[M100TURBOFR]

Joao Yes Section EMK6 Intermittents but still non the wiser. I'll clean up the ALDL terminals and see what it gives.
David

[Tuga2112]

Joao Yes Section EMK6 Intermittents but still non the wiser. I'll clean up the ALDL terminals and see what it gives.
David

what about EMK 4-52 ??

that section is specific about code 42 theres a flowchart there of diagnosis approach. maybe that can be helpfull.

i have never read the the details about the internal workings of the electronic spark timing. but i would assume there is a relationship between the ignition module and the CAS probably more looking in the direction of the CAS because the description includes the word "timing".

but if i was having that trouble, (apart from obivously asking here if someone else had the same issue), i would have a read about those 2 components and how they relate to code 42. probably also just check if their wiring and grounding points are all in good condition.

im afraid i cant help more without making myself familiar with those parts.