Bump, still needing an answer.

 

I've seen the connectors on the coils go bad.

 

I guess the plugs could get nasty. I will try and clean out the plug real good.

I am really needing to get to the bottom of this as I think this truck may be getting sold.

 

did you swap the coil packs with a known good one???

 

Yes we did still no spark.

 

Time for a compression test...

 

I guess I could do a compression test, but I still think it is something in the wiring.

 

Unless your continuity checks were inconclusive, which you claim they weren't...then it isn't in the wiring.

So, you said that you were getting intermittent spark to #5, yet the wiring itself checks out. That points to the PCM as the problem. However, single cylinder failures due to a fault in the PCM are extremely rare. Do a compression test to ensure everything mechanical is good.

 

Yeah I will do a compression test to see. The strange thing is it ran good, it never seemed to lose power.

 

Ok... we found the problem... the new plugs I put in, the tip on number 5 must have got broke when I pulled them out to put antiseize on... I feel like an idiot!