Misfire

I have a 2000 LS, it putt-putt sometimes and when going up hills, the check engine light is now on. The dealer wants to charge $60 just to look at it. Someone said the screw could be loose causing oil and water to mix. Could this be fixed easily? (Help) :banghead:

Autozone will read your ODBII engine code for free - then you'll know what is wrong.

could be clogged fuel filter, could be bad coils, ... lots of things...