Greetings,

I am hoping that someone can help me with the diagnosis of my 1999 Mitsubishi Eclipse GSX.

OBDII reports diagnostic code Po303 - misfire in cylinder 3
Fairly smooth at idle and high revving when out of gear
Revving is always rough at low portion of rpm curve
Misfiring at low rpms when in or out of gear
Rough with power loss when in gear, especially under load or with heavy throttle (from start, uphill, or when floored)
Will drive almost normally if I'm _very_ gentle with the gas pedal
Flooring it when in gear results in deep low tone, rough vibration, and flabby power

Can anyone make a suggestion based on my symptoms?

Thanks!

 

change your spark plugs and wires and that will probably fix the issue

 

Any idea whether it could be a fuel injector?

 

not really... its either that or the coil pack... trust the engineer

 

Injectors and coilsusually aren't a parts that fail often, listen to TE and change your plugs and wires.

 

I had the same thing.. Except it was misfire on cylinder 1.. Ended up being the spark plug wires.

 

Great! I already ordered plugs and wires, but just wanted to make sure in case other parts might be necessary.

 

And the winner is... Spark plug wire #3

Changing plugs and wires solved the problem. Thanks!

 

yeah i had the problem of oil getting into my number 2 cylinder due to a torn sparkplug boot, andwas causing a bad misfire, so finally i replaced the wires, cleaned the oil, ran like a champ.

 

glad to hear it.