P0300 Random/Multiple Cylinder Misfire Detected WTF?!!

[longhornsqx4]

Well my Pathfinder has been running like absolute crap upon startup for the last week, sounded like it was bogging/misfiring, well today it finally threw a code

P0300 Random/Multiple Cylinder Misfire Detected

Once the car warms up it runs alot better, smooth anyways and not all choppy like on startup, but my idle seems screwed up aswell, if your at a stoplight sometimes the rpms drop to low and the car stalls.

This all started after I disconnected my battery overnight, connected it in the morning, then this happened.

I have no idea where to start, or what should be possibly checked, diagnosed first.

Any help appreciated, as this car is my bread and butter.

[fueler]

i first thought spark plugs but then you said it all started when you unhooked the batt overnight. are the battery terminals on nice and tight ?

why did you unhook the battery overnight ?

[nnorton44]

I've had P0300 for a while now, from the research Ive done start with the plugs then look into ignition coils.

[Chuck Tribolet]

From the FSM, P0300 causes include:

Improper spark plugI Insufficient compressionI Incorrect fuel pressureI The injector circuit is open or shortedI InjectorsI Intake air leakI The ignition secondary circuit is open or shortedI Lack of fuelI Drive plate or flywheelI Heated oxygen sensor 1 (front)