CEL Code after plug and wire change

[James Neumeier]

I stopped by my local shop this morning to have the code read, and he came back with P0301 and P0316. As several of you know this started after I changed my plugs and wires over the weekend. I have put a new coil pack on order just in case. I cleaned the sockets on the coil pack and the #1 socket still has a spark trying to creep out with the wire unplugged.

 

[Tom Schindler]

P0301 = Cylinder 1 Misfire Detected



P0316 = Engine Misfire Detected on Startup (First 1000 Revolutions)



You said something about a spark jumping at the coil. Plkease try to explain in better detail. When you first mentioned it, I had a hard time trying to decipher what you ment.





Tom

 

[James Neumeier]

In my trouble shooting efforts, I was unplugging the wires at the coil pack to determine which cylinder was misfiring. When I inplugged cylinder #1 there was a small faint arc firing to the inside of the socket for the #1 cylinder on the coil pack.

 

[Tom Schindler]

You were doing that with the engine off?





Tom

 

[James Neumeier]

It was running. I was trying to eliminate the plugs and wires as the cause. When I removed any of the other wires (one at a time) it really started to miss. When I removed the #1 wire the engine changed slightly, but definately not as dramatically as with the other wires removed. That's when I noticed the spark on the inside of the coil pack socket.

 

[Tom Schindler]

From my experiences. IIRC, there are 4 wires going to the coil. One is a ground, and the other three are signal wires.



Two cylinders fire at the same time.



I do not think the coil is the problem. I say your plug is bad. My reasoning is this. Thecoil is firing. That is why you are misfiring on one cylinder. If the coil was bad, you would get a CEL on two cylinders. The wire could be bad, but I am leaning towards the plug.



Have you replaced the plug on the cylinder misfiring? Another thing to do is switch the number 2 wire with the number 1 wire, and make sure you switch them at the coil too.



If the misfire moves to the number 2 cylinder, then the wire is bad. If it stays at the number 1, then the plug is bad. If you replaced the plug and it still shows a misfire, the coil could be bad, but honestly, I think the coil is fine.





Tom

 

[James Neumeier]

I replaced the #1 wire with the orginal wire and the same sympton persisted. I will switch the #1 and #2 plugs tonight before I replace the coil.

 

[Todd Z]

you may have a dirty injector.... Have you changed your fuel filter???



Also as stated above check the coil pins and wires going to it, make sure they are ok also..



I think you have a fuel issue if you switched wires and plugs and stuff is still messed up..

Todd Z