SC running lean after 30 nin
 

After 30 mins of motorway driving or 50 mins of local driving, my 79 euro SC starts to run lean. I can't figure why. Surely all the warm up bits are fully warm after 10 mins? Only thing I can think of is a faulty AAR that is warming up by engine heat instead of electrical power. What do you think?

Not sure if my AAR analysis makes sense ...

When I re-adjust mixture to correct values after 1 hour driving (definitely hot), then I get low idle rpm and lean on warm restart and for the next 15 mins of local driving.

Do all the maintenance items like new fuel filter.
one possible scenario is it runs lean on the normal injectors always. But when the engine senses cold it enables the cold start warm up circuit. which will richen it up enough to run.

How are you aware of lean running? wide band AFR meter?

Yes, the LM2 with wideband sensor. A great piece of kit for the CIS.

This should really go in the 911 forum. Here, let me move it for you.

--DD