2001 A4 2.0T tip oil light question

[Douglas Fifield]

My GF has the above car bought used last summer.  The oil light comes
on regularly.  Here is what she has told me:

- oil level is good
- comes on after warm up and going up hill
- does not come on when cold
- does not come on going downhill or on level

I don't have a VAG reader so can't pull codes.  The check engine light
is also on most of the time.  Repeated visits to local qualified
wrench have not solved the problem.

Looking for suggestions.  The oil light is the one that bothers me the most.

D.

-- 
Douglas in MN
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