DTC ? Ignition coil 6 control circuit

[70ls1chevelle]

My car has a misfire that you can only feel now and then,maybe doing it all the time not sure,mainly feel once its warmed up and under light acceleration it misses and pops,im assuming the problem is when the code pops up in dtc's
(PCM)P0356-Ignition coil 6 control circuit (old) (immature). I have changed tried changing all coils and coil harness,that coil only,i used an ohm tester and checked the coil harness,and the motor harness all the way to the ecm and both checked out good,tried shaking harness still good. Any help cant get this code to stay off dtc's and the misfire ?

[mecanicman]

What year pcm/harness/engine is this from?

[70ls1chevelle]

There both from a 99 firehawk

[mecanicman]

Here is the trouble shooting guide for that code. I have had to replace PCM's for this before.

[70ls1chevelle]

Any other ideas,need to fix this ? Thanks

[mecanicman]

Complete diagnostic is in the pdf, follow it through.

[70ls1chevelle]

Complete diagnostic is in the pdf, follow it through.

Ok i will,alot of reading lol