Hello Audi members

i have a 2001 audi a4 1.8t manual

It seems to have a leak in the main seal and possible others since its at 170k miles.
Along with that it also has the P0171 code for system too lean

and also the misfire of engine and even after i replced the ig coils the system still says that.

Any feedback would be great thanks everyone!

 

The misfire and the 'system too lean' issues may be the same issue.

Check for vacuum leaks and clean the MAF (with MAF cleaner). Those are the two cheapest places to start.