Hey guys Daniel from Georgia here.
Our 2018 Yukon had a P0307 code last month so I replaced the ignition coil and it seemed to fix the problem until last week it started again. I swapped the new coil (on#7) with the #1 coil. This produced a P0300 code (random misfire). I then pulled the valve cover and reconnected the ignition coils and plug wires. I started the engine and noticed that all the lifters were working like they should.
This morning I’ve been checking plugs and plug wires. All the plugs were in good shape and produced a good spark except number 7. It was a little “dirtier” than the others and made a noticeably weaker spark. I cleaned it up a little with a towel and swapped it out with the #1 plug. It then produced a nice strong spark and now the plug from #1 currently in #7 is making a weak spark. So I swapped plug wires and still getting a weak spark on#7. The only other thing I haven’t checked is the ignition coil connector/plug. Is there a way to check that it’s producing the right voltage or signal being sent to the coil or should I be looking for something else? Thanks
Our 2018 Yukon had a P0307 code last month so I replaced the ignition coil and it seemed to fix the problem until last week it started again. I swapped the new coil (on#7) with the #1 coil. This produced a P0300 code (random misfire). I then pulled the valve cover and reconnected the ignition coils and plug wires. I started the engine and noticed that all the lifters were working like they should.
This morning I’ve been checking plugs and plug wires. All the plugs were in good shape and produced a good spark except number 7. It was a little “dirtier” than the others and made a noticeably weaker spark. I cleaned it up a little with a towel and swapped it out with the #1 plug. It then produced a nice strong spark and now the plug from #1 currently in #7 is making a weak spark. So I swapped plug wires and still getting a weak spark on#7. The only other thing I haven’t checked is the ignition coil connector/plug. Is there a way to check that it’s producing the right voltage or signal being sent to the coil or should I be looking for something else? Thanks
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