Misfiring issue. Coil 6 code
Thread Starter
Teching In
Joined: Oct 2017
Posts: 17
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From: San Francisco CA
Misfiring issue. Coil 6 code hey guys I have replaced the spark plug coil pack and wires and I have yet to fix my missfire problem. I keep pulling a coil six code And have delayed throttle response and loss of power. My only other idea is to Change the harness for the coils? I could use all the ideas/help as I’m running out of ideas. The car is a 99 ss with an Ms4 cam & PRC heads. Thoughts ??
What is the actual code number you’re getting? You can also try swapping spark plugs with a different cylinder to see the the code follows the plug our stays on #6. Swapping the coil pack harness is a good idea too.
Thread Starter
Teching In
Joined: Oct 2017
Posts: 17
Likes: 0
From: San Francisco CA
The code is p0356. I’m waiting on the harness but I doubt that’s the problem. It seems in decent shape from the looks of it. I will take a look at the coils even though they are all new(just did a motor swap 2 weeks ago). Thanks for the help let me know what you think about that code
I can’t remember if the coil sub harness connectors are different between the left bank and right bank... but if they’re the same you could try swapping your existing coil sub harnesses and see if the code goes away or moves with the harness. I would still swap the #6 spark plug with a known good plug and see what happens. It’s a quick easy test. Worse case scenario the pcm stopped sending a signal to that coil, but I would start at the plug (confirm you’re getting spark) and work your way back.
Thread Starter
Teching In
Joined: Oct 2017
Posts: 17
Likes: 0
From: San Francisco CA
So I removed the existing harness and put in a new one and now I’m getting codes for all coils on that side... I’m so confused. Can you even put the harness on wrong ?? I’m not sure if I’m just having bad luck or what. Any ideas ??
Check the wiring harness that feeds that bank coil subharness. It’s possible you have grounded or loose wires from the pcm bulkhead that feeds that bank of coils. I suspect when you moved the connectors to plug in the new coil sub harness, it made the wiring defects worse and now you’re seeing the effects.
