Possible valve cover gaskets are leaking oil onto the plugs and the oil is getting into the cylinder. The oil can also short the plug wire and damage the plug wire causing the check engine light to light.
Trouble code P0303 means:Cylinder 3 misfire detected
A flashing check engine light means an engine cylinder misfire has been detected
Check Coli, an wires attached to coli, coli my not be getting enough juice
A flashing check engine light is usually due to a misfire. see related questions below.
on the millenia missfire, check your catalytic converters it has 3 chances are one or more has fallen into pieces in the pipe where do people come up with guesses like these? random miss on a millenia is most likely electrical. definitely NOT cats. if you have a 2.5, check your ign wires, spark plugs, and ign distributor. if you have a 2.3, check plugs and coil packs
Start with a bad Spark Wire Followd by a new Distributor Cap and Rotor button. Pening that failure, replace the sparks.
check wire routing,order, or if replace is needed, after that check compression, head gasket,or crack in head.
possible it could be the cam shaft position sensor or it could be the control module in the distributor.
p0302 is cylinder 2 misfire, you need to fix the cause of the misfire. Possible causes are plugs, coils, injectors......
check for low fuel pressure (its critical) with guage on schraeder valve on fuel pipe on rear of engine in cab drivers side , should be around 55psi
what are the possible causes of misfire on number one cylinder in a dodge 2003 ram 4.7 liter engine
its most likely the air by pass valves and some coils that need to be changed.