Sounds flat!

[E30WES]

Just got my car back from the garage where its been stored for the last six months. Had a flat battery and wouldnt turnover when I got there. Out come the jump leads and she fired up straight away! Bonus. Driving it back though it seemed down on power in the lower rev range and general doesnt sound like it fireing on all six? Why is this? and how can I remedy the situation? Any guidance would be appreciated chaps...thanks alot.

[Speedtouch]

Could be that the ECU needs to relearn its settings - try giving it an Italian tune-up/damned good thrashing.