Got code P0353 So I.... 2008 explorer EB v6 4.0

[jdxprs]

today, my truck was running terrible and had no power. i left it run in the driveway for about 20 minutes, and finally a check engine code came in.

The code was P0353. Ignition coil C Primary/secondary circuit malfunction.

i pulled the wires off the ignition coil one at a time, and on the two in the middle, which are wires 2 and 6, i had no spark and there was no change to the way the engine was running like there was when i pulled the wires off the other 4.

I went and picked up a coil pack and installed it. When i started the truck it ran perfect for about 5 minutes, then the problem came back. same thing. running really rough and no power.

about 2 minutes later the problem stopped and the truck ran perfect again.

This is happening on and off now. it keeps coming and going. the computer spit out the same code again 1 time when it was running rough, but the truck started running good again and i was able to clear the code and it hasnt come back yet.

The only things I can add to this, is that the truck was very low on gas. down to 15 miles to empty when this started. i have since added fuel injector cleaner and filled up with gas.

The other thing, is if i get on the highway with it, and gun it, i can hear a couple of popping sounds from the engine like a quiet backfire.

the truck has 83,000 miles on it.

CAN ANYONE HELP??? I've searched the forum and seen others with similar problems but i cant find any SOLUTIONS or CAUSES.

 

[Themightyquinn]

did u pull the spark plugs, and when were they replaced

 

[jdxprs]

did u pull the spark plugs, and when were they replaced

no i didnt. i figured since the coil replacement brought spark back to 2 and 6, that the plugs and wires must be ok. am i wrong?

 

[jdxprs]

ok. i replaced the plugs and wires tonight. truck is still running terrible. no codes are showing.

i started looking around to see if i could find a vacuum leak or something and i found a wire sparking against a metal bracket that holds the large group of wires.

the wire is all white and appears to go to either the top or bottom wire harness that connects to the pcm.

I tried to track the wire but was unable to. i did notice that there is an all white wire that is connected to the wire harness that goes into the ignition coil pack. if it's the same wire, that would explain what caused the coil to go bad.

should i try replacing the coil again now that i have repaired that wire?

are there any fuses associated with the wires to the pcm or coil?

does anyone have a wire schematic of the pcm harnesses?

 

[jdxprs]

update...

still running like ****.

when i pull the wires off the coils, im getting sparks on all of them.

however, when i pull the wires off of cylinders 2,6 at the coil, the engine stays the same.

when i pull the wires off of cylinders 1,3,4,5 the engine runs even worse.


someone please help!!!

 

[Themightyquinn]

How badly was that wire damaged? was it chewed through at all? How did you repair it? I should be getting my wiring diagram book mailed to me soon for my 07. It should mainly be the same as yours since you have a V6 also. When I get it I will snap a pic of the schematics and post it for you.

 

[jdxprs]

There were about 5-10% of the strand cut.

I put a splice in the line.

 

[jdxprs]

No ford techs around???

 

[jdxprs]

update...

last night, i replaced the coil again, replaced the plugs on cylinders 2 and 6, and i wrapped the hell out of the the group of wires near the pcm that had the damaged wire.

In case anyone else ever goes through this, i want to explain where the group of wires is that caused my problems. On the passenger side of the truck, back against the fire wall is the PCM. There are 3 wire harnesses attached to the PCM. If you follow the wires off the top and bottom harness, they come toward the front of the truck, then bend hard and head back toward the firewall as one bigger set of wires. Right next to the pcm, they are attached with a plastic push pin to a metal bracket. After leaving the metal bracket the wires go up and to the right, towards the driver side back at the fire wall.

The top of the wires on that metal bracket rub hard against the bracket because of the angle of the wires. That rubbing wore out the wire insulation and led to the powered wire going to ground on my truck. It was hard to see the spark because the wires were pressed so tightly against the bracket. If you have to replace a coil pack, i would definetly check those wires!!!

as of right now, it's running good but im not getting my hopes up until i get at least a week of no problems. If I don't report back to this thread, everything is fixed.

 

[bbrown702]

update...

last night, i replaced the coil again, replaced the plugs on cylinders 2 and 6, and i wrapped the hell out of the the group of wires near the pcm that had the damaged wire.

In case anyone else ever goes through this, i want to explain where the group of wires is that caused my problems. On the passenger side of the truck, back against the fire wall is the PCM. There are 3 wire harnesses attached to the PCM. If you follow the wires off the top and bottom harness, they come toward the front of the truck, then bend hard and head back toward the firewall as one bigger set of wires. Right next to the pcm, they are attached with a plastic push pin to a metal bracket. After leaving the metal bracket the wires go up and to the right, towards the driver side back at the fire wall.

The top of the wires on that metal bracket rub hard against the bracket because of the angle of the wires. That rubbing wore out the wire insulation and led to the powered wire going to ground on my truck. It was hard to see the spark because the wires were pressed so tightly against the bracket. If you have to replace a coil pack, i would definetly check those wires!!!

as of right now, it's running good but im not getting my hopes up until i get at least a week of no problems. If I don't report back to this thread, everything is fixed.

Make sure you wrap those wires up real good with wire loom. If they're still rubbing a little piece of hose cut down one side, and slid over the bracket should help. Sounds like you may have figured it out, can you post a picture of the wires you repaired so we can get a good idea of where, and what. The only thing I could add is put a spark tester gapped to your specs on each wire, and check for a bright blue spark, and check running fuel pressure. Fuel pressure that's even a little low can cause some weird stuff to happen with an engine.

 

[jdxprs]

thanks. i'll try to post pictures tomorrow.

 

[jdxprs]

I placed the point of the pencil on the spot that went to ground. You can't see the metal bracket the wires are attached to because it's blocked by the wires.

 

[jdxprs]

as you can see, i wrapped it up pretty well.

i went with a fabric high temp exhaust wrap, and then covered it with damn near a whole role of electrical tape.

as long as my splice holds up, i think it will be fine.

 

[Boomyal]

Good work JD. Those kind of problems can be hard to find. I am generally impressed by the way Ford runs all of it's wiring. I guess they didn't do justice, in this case.

 

[jdxprs]

when i think of the original code i got, i wish i would have known the white wire on the coil harness was for cylinders 2 and 6. matched that with the code, i could have put a meter on that wire and figured out there was a short in the line.

 

[DBmac31]

I placed the point of the pencil on the spot that went to ground. You can't see the metal bracket the wires are attached to because it's blocked by the wires.
I am experiencing the very same problem right now. Do you still have the pictures of the wires from the PCM? It would be useful to see now.

 

[DBmac31]

I am experiencing the very same problem right now. Do you still have the pictures of the wires from the PCM? It would be useful to see now.

How do I view the pics?