I have a 05 E350 5.4 (150K) Had a miss on #4 R bank. so I replaced the plug and cop, lasted just a couple hours. Miss is back on same cylinder coil went out again. Went ahead and replaced all the cop's with NAPA brand and the plugs. Ran great for a day and the number 4 coil is out again. Another thing is once the miss is picked up it also cuts off the A/C. So does anyone have any idea why #4 cop keeps burning out on me. I got a Innova scan tool but was told it will not work on heavy duty trucks, do I need to take it to the dealer to have the codes ran? My scan tool says a generic code of PO354 coil D... Coil D??? My Ford car will at least say misfire #4 cylinder.
compression 150lbs
So any help hear



Thanks
Jim

 

Coil driver fault . Ck connector at coil . Make sure it locks on properly . Ck for corrosion at plug . Ck wiring to coil for broken wires , shorted wires . Could be a bad coil driver in pcm . I see a lot of the coil plug locks break . I would ck that first .

 

By the way , looks like your code reader is working .

 

Had a lock on the other bank that was bad put a wire tie on that one. Also just had the transmission rebuilt about a month ago. Don't know if that applies to this problem. There's a red power and white wire to the cop plug.Is there a way of checking or back probing the wire. The white one should produce a pulse red should be power.The PCM was the only other thing I could think of. Tried to run a KOER test with my scan tool it would not complete the test. Could that also be the PCM problem?Thanks for the responseJim

 

With a wiring diagram you can find the driver wires at the ecm and ck for cont. Do wiggle test , ect . A lot of times KOER test will not complete if a fault inhibits it from running .Coolant temp , hard fault , ect . Preform KOEO , and stored codes . Fix KOEO first , go from there . Probably does not apply , but there was an issue with coolant on top of the coils , eating through the potting and shorting the coils . I think it only applied to Expey and F series . But should not show up so soon .