Now I have a PO357 code

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Nov 3, 2019 | 04:28 PM

traildad

Thread Starter

Mountain Pass

Joined: Apr 2013

Posts: 101

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Now I have a PO357 code

My 02 f150 with 5.4L had a leaking intake manifold. I replaced that ok but now 5 COP connector plugs will not lock onto the coil. It ran good when I first started it but that didn’t last. As I was driving it started running rough and a service engine soon light came on. I assume it’s missing even though my scan tool doesn’t indicate any cylinders are missing. My Blue Driver scan tool shows the code definition as “Ignition COP 7 Primary/Secondary Circuit Malfunction. Am I right to assume it is telling me the problem is on the #7 cylinder? If so the #7 cylinder plug is one that still locks on.

I dont know if this this is connected but it seems that the AC stopped working even though I had a new compressor installed a month ago and it worked fine. It was working after the manifold repair but seems to have stopped after I put zip ties on the plugs with broken locks.

Any suggestions?

Nov 3, 2019 | 06:02 PM

Bluegrass 7

Lead Driver

Joined: Sep 2006

Posts: 7,907

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Electrical open circuit on cylinder 7 coil.

Nov 3, 2019 | 07:17 PM

traildad

Thread Starter

Mountain Pass

Joined: Apr 2013

Posts: 101

Likes: 4

I replaced the one I thought was the problem with some extras I have which didn’t help. Then I swapped it with the one next to it and that didn’t help. Then I figured out that when I looked at the cylinder numbers on my phone I read it upside down so I was working on the wrong cylinder. Then I checked the actual #7 and it wasn’t even plugged in. I must have missed it when I was adding the zip ties. I’ve got it back together and I think it’s better. I’ll test drive it now. Thanks for the help.

Nov 3, 2019 | 07:34 PM

traildad

Thread Starter

Mountain Pass

Joined: Apr 2013

Posts: 101

Likes: 4

Ok, much better. A quick drive and the error code didn’t come back. I’m erasing the pcm again so I can train it while all the cylinders are working. Hopefully this will finish the job.

Nov 3, 2019 | 09:10 PM

traildad

Thread Starter

Mountain Pass

Joined: Apr 2013

Posts: 101

Likes: 4

Finally it’s working. I don’t know how well the zip ties will keep them plugged in over time. I ordered what is listed as motorcraft OEM COP plug plastic housings. Pull the wires out of the old plugs and stick them in the new plastic housing and you’re good to go. Only $20 for a set of 8 so I hope they’re really OEM. If the zip ties don’t stay tight I’m ready with a real fix.