This code says misfire on cyl #3 so I changed the plugs & wires that didn't help. New coil pack, that didn't help. Any ideas out there? When the engine is cold it starts fine but after driving then letting it sit for 30 minutes next time I start it the check engine light starts flashing and the engine shakes real bad then turns solid. After that the engine seems to run fine until the next time. I heard that it could be #3 fuel injector but if so why does it run ok even when the check engine light is on? Any advice would be appreciated.

Mike

 

how did the plug on #3 look when you pulled it out, compared to the rest of them?

 

Possible causes for P0303

* Faulty spark plug or wire
* Faulty coil (pack)
* Faulty oxygen sensor(s)
* Faulty fuel injector
* Burned exhaust valve
* Faulty catalytic converter(s)
* Running out of fuel
* Poor compression
* Defective computer

 

Nothing different with plug #3, they all looked the same.

 

How did they look?

 

They all looked dark grayish in color. No oil or carbon either.