I got a 2000 accent, it runs really bad like it won't even go it sputters so bad, we were having problems about 6 months ago and had the pluggs and wires changed, now it does it again really bad, so i scanned it and I got P0300, P0301,P0302,P0303, witch is misfires, but when I unplugg the MAF sensor it runs pretty good, well enough to drive it, so any help would be good, I am a diesel mechanic so I can do most things to fix it just not to familiar with gassers, thanks for the help

 

P0300 = Random/Multiple Cylinder Misfire Detected
P0301 = Cylinder 1 Misfire Detected
P0302 = Cylinder 2 Misfire Detected
P0303 = Cylinder 3 Misfire Detected

First, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how old they are, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest new spark plugs and wires. Otherwise, check the coils (a.k.a. coil packs).

In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

However, since you are getting multiplemisfire codes from a bunch of cylinders thecause could bea lean fuel condition, which woudl explain why the car runs better with the MAF disconnected. Checkfor avacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.