My sister'* 00' Cavalier has a pretty nasty miss in it upon take off.. Idle is about normal, and higher RPM it smooths out, just high load/low rpm/take off.. I replaced a coil pack and plug wires last night (the other coil pack was replaced about a year ago).. Didnt seem to help at all. It was throwing a cylinder2 miss-fire code before I replaced those parts. Now throwing a random miss-fire code..
Any ideas on whats going on?

lol i thought this thread was going to be about a stolen Cavalier. is the PCM throwing any codes ?

can't edit my post , is the code for the random misfire the same cylinder, could be an injector, unless you have TBI.

I assume it is now throwing a P300 code. On a random misfire, I would start by checking fuel pressure. When was the last time you changed the fuel filter? How about the fuel pump?

You would be correct on the code.

Fuel filter not since she'* had it (3 years)

Fuel pump- We haven't, so I'd assume 135,000 miles ago when it was installed at factory

I guess and fuel pressure check is in order....

I would change the fuel filter first, then check fuel pressure.