I'm fairly certain that I have a COP issue with my 5.4L engine. Has 150K on engine and I just replaced all plugs, boots and 5 of the 8 COP. Also replaced the usual bad PCV hose for the second time. Engine bucks at 50 MPH under very mild acceleration. No codes yet. Question.... I replaced 5 COP and used the ones from Auto Zone since Ford wanted $100 per coil. Did I shoot myself in the foot? I feel as though I'm limping around with only 5 toes remaining! If anyone has experienced similar issues, please let me know. I'm about ready to replace all 8 with good quality COP's. Any suggestions as to where to buy and what brand? Thanks.

 

It is quite common for COP's to be on teh blink, and not show a CEL.

Our new Ford COP’s, the Sultans of Spark(S.O.S.), have
been designed with both durability and performance in mind.

Please see them at:

http://www.performancedistributors.com/soscoils.htm

Quality was the main feature we stressed when we went to the
drawing board on these coils.

By the way, for those of you who only need to replace a defective coil,
our SOS Coils are available separately.