I plugged my code reader in and it came up with P0302 code and my second cylinder is not firing. What could this be?
have the same problem?
Monday, December 19th, 2016 AT 1:16 PM
It could be a bad/fouled spark plug, bad plug wire, distributor cap could be carbon tracked, Number two fuel injector could be inoperative, plugged or the control circuit to it could be bad. Or mechanically you could have low/no compression or a bad cam lobe not opening one of the valves.
Start with the easy stuff first. Remove the plug and check it. If you find that it is damp with gas the likelihood is that you have a problem on the ignition side.
Clean it off and swap it with the plug in the number three.
Clear the code - Do you now get a misfire for cylinder three?
Yes - Replace the plugs as they do wear out and on a turbo they will stop firing under the higher cylinder pressure faster.
No - Swap the plug wire with number.
Clear the codes - Did the code change now?
Yes - replace the wire (or wire set) as it is faulty
No - Remove the distributor cap and check it for cracks or carbon tracking, if you find either replace the cap. Carbon tracking cannot be removed well enough to ensure it does not return.
Clear the codes and see if they stay gone.
If none of that removes the code. Connect a noid light to the injector connector and see if the injector signal is there. If it is swap the injector to a different cylinder. Do you still get the same number two misfire? If not the injector is likely shorted or plugged. Replace it.
If you do all the above tests and find the plug swap, wire swap and the cap all looked good. The injector test and swap did not change the miss. Run a compression test and see what you have.