P0303

[AK04SS]

Hey everyone,

I've been having this P0303 code on and off lately. I did plugs and wires before winter and the code would come and go. Last week I replaced the number 3 coil and it went away for a week and now it shows that P0303 is pending again. Is there anything else I should look into?

 

 

I also have a bluetooth obd2 plug that I can use with the Torque app.

[EXGM]

I wonder if you have an issue with the engine harness at the coil. I would look for any kind of damage to the plug for the coil, make sure the wires and pins look ok. I wouldn't keep throwing parts at it. I don't know how many miles you have it might not be a bad idea to do a compression check on that cylinder to rule out anything with the hole. Your now at a point your going to have to start doing some good ol fashioned diagnosising now. Me guessing without seeing your truck through the ol interweb is it's a wire harness issue. It was fine for a week after you disturbed the coil connection. Your gonna need to check the wiring with a volt meter and make sure you don't have a broken wire somewhere or that the coil is getting correct signals and voltages. If that's above your technical abilities it may be time to seek a professional.....

[BlueAKSSS]

I agree with what Matt said above, I would start with a simple compression test and make sure you have decent compression in the cylinder. I also agree that there is a high chance it could be just an electrical connection to the coil pack. Let us know what you find!

[AK04SS]

my truck is right around 146,500 miles. i can diagnose it, just don't have the time. I'll probably have my mechanic friend check it out for me. It seems like the code comes and goes. I started the truck up today and my ultragauge didn't show that the code was pending again.