Coil!

Finally got time to work on the truck last night. Pulled the plugs, they were fine. Ohmed the plug wires, they were fine. Compression test indicated some ring wear on the left (1-7) bank. Right bank was fine which seemed a little odd, but ok i'll take it.

Checked the coil, primary restistance was 2.1 ohms. Out of spec. Stores were closed by then so I went early this morning and bought/installed a new coil.

Truck is running smoothly and no codes on the drive in. I'm hoping it's fixed.

Thanks to all who helped!

Tom

 

If the left bank numbers are more than 10% off compared to the right side, it's time for a rebuild.

 

Spoke too soon. Went to lunch. The misfire is back at all temps. Now the only code is P0301.

Injector? Resistance is in spec and when I listen to it it has a regular tick like it should.

Thoughts?

 

I have about the same issue with my truck as well. been working at it for about 3 months now. Have had the p0300 code as well as every code for every cylinder(po300-po308) all at once. Reset the codes and they never came back. I have not done a comp. check but have tested just about everything else. With the help of people on here Heyyou and cmckenna. I think we have it narrowed down to plug wires or a bad coil. Now my dad gave me a brand new coil he bought for his 5.2L jeep he sold. When I put it in and took it for a cold 2 mile drive it worked perfect. I would take a close look at the plugs and wires. With Recommendation from cmckenna I would use the magnacore wires. They don't need to be run a special way and seem to be a great quality wire..waiting on a set now. I'll let you know how they are when I get them. Also use the NGK V-power plugs. good luck and keep me updated if you beat it.

 

Pull the plug on 1, and see what it looks like. If you really suspect the injector, swap the 1 and 3 injectors, and see if your miss moves with it.