Hey guys,

My car threw a p0303 today. I was driving it pretty hard. Parked it, all good. Then I came out about 30 min later to go to the store. Turned my car and drove for about a min and my cars ses light came on... p0303... Cylinder 3 misfire. What would cause this? After I erased the code it didnt come back but I only drove a few miles and drove it easy.

A google search didnt really didnt give any results/answers.

Thanks for the help in advance!

 

Possible causes that I found:

Faulty spark plug or wire
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector
Burned exhaust valve
Faulty catalytic converter(s)
Very low fuel
Poor compression
Defective computer

 

It could be your spark plugs. If you haven't changed them they could cause your engine to misfire.

 

Check the conditions of your plugs. If the plugs seem OK or you have replaced them mark the Coil and swap it to a different cylinder.

Drive and if the different cylinder now comes up with the Misfire it's probably a bad coil.

If the misfire still occurs with cylinder 3 with new plugs then a faulty fuel injector could be at fault.

Start there and let us know.

 

same issue and i swapped my cyl#1 coil to a different location like technic stated and it followed. So i bought a new coil and the misfire came back a week later. I was convinced it wasnt the coil causing this but i broke down and upgraded the stock coil and havent has an issue for 3 months now. If it does follow when u swap coil there is someone selling stock coils for 100$ for 5 under the FS.