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Topic: P0351, likely bad coil (Read 248 times) previous topic - next topic
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P0351, likely bad coil
2017 E450 running rough, with code

P0351 "Ignition Coil "''A"'' Primary Control Circuit/Open"

Indicating a bad ignition coil.

Problem is I’m a good 100 miles from reasonable repair choices.   How bad is to drive a couple hours missing one cylinder?

Also, any mechanic recommendations for Pittsburgh?

Thanks

Dave
Dave

2017 TK
Re: P0351, likely bad coil
Reply #1 –
How good are you as a mechanic? Any Auto Zone or O’Reilly’s will have a coil. Lots of You tube will explain the major but doable job of replacing it.
Harry 2006RB
Re: P0351, likely bad coil
Reply #2 –
Quote from: hbn7hj  - 
How good are you as a mechanic? Any Auto Zone or O’Reilly’s will have a coil. Lots of You tube will explain the major but doable job of replacing it.
Not good at all as a mechanic.

I might have a spare, but coil 1 is a pain to get to, I can barely reach it from the front.
Dave

2017 TK
Re: P0351, likely bad coil
Reply #3 –
Once the engine cooled off, it’s not misfiring.

Temped to inch closer to Pittsburgh rather than hope to find anyone reliable two hours south.
Dave

2017 TK
Re: P0351, likely bad coil
Reply #4 –
I just had coil 8 and all spark plugs replaced. No, I did not do it. $1500. I might try the next one. Coil 1 should be the easiest but still not trivial.

I drove 50 miles home with no complications.
Harry 2006RB
Re: P0351, likely bad coil
Reply #5 –
Hi Dave;  I'm hoping that would explain those misfire codes that no one could locate.  Don't drive on the missing spark on that cylinder. Larry Wade had a sparkplug blow out, plugged the hole up and forgot to disconnect the fuel injector. That would be similar to driving with no coil.  The injector kept going and washed the oil off the cylinder wall. That scuffed the cylinder bad enough to scrap the engine! (that would be up in the $6k+ range!)  If you needed to you could unplug the injector. With no gas and no spark, at least you don't have a hole there. You might be able to safely drive quite a way without damaging the engine.
    With 9 good cylinders and a lighter weight coach, no towed, you might not notice any difference.   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: P0351, likely bad coil
Reply #6 –
Update:

We drove ALOT of steep grades up and down in West Virginia today.

The engine sat a good 60-90 minutes while googling and updating here.


Then decided to limp four miles to a Walmart and call it a night.  Or so I thought.

The misfire was gone and AC was working once again.  Decided to push on another 35 miles to tonight’s campground, turning around or boondocking somewhere if the misfire/running rough returned.   It didn’t, but the AC did run warm for a bit up a steep hill, but the misfire didn’t return.

Research found when you get a P0351 it can disable the a/c due to the misfire, which jives because the AC stopped working when the engine was running rough.

So the plan is to baby the engine, keeping a keen ear out for misfires (running rough/loss of power) to get to Pittsburgh, about a hour) to find a mechanic

Also thinking the high revs of up and down hills stressed (overheated) the coil?
Dave

2017 TK
Re: P0351, likely bad coil
Reply #7 –
Quote from: RonB  - 
If you needed to you could unplug the injector. With no gas and no spark, at least you don't have a hole there. You might be able to safely drive quite a way without damaging the engine.
    With 9 good cylinders and a lighter weight coach, no towed, you might not notice any difference.   RonB

Good idea, will keep that in mind.

Now I just need to find instructions for that.
Dave

2017 TK
Re: P0351, likely bad coil
Reply #8 –
Quote from: RonB  - 
Hi Dave;  I'm hoping that would explain those misfire codes that no one could locate.
I’d like to think so, but not really.

5k miles into the issue, all the coils and plugs were replaced in Anchorage, didn’t resolve the issue, cylinders 2 4 6 7 9 still reported misfires without running rough or loss of power.  All the wire harnesses are well connected.

Though this P0351 is something new, maybe I’ll get lucky this time, though I’m not holding my breath, I’ve had really good mechanics tear out their hair.
Dave

2017 TK
Re: P0351, likely bad coil
Reply #10 –
Quote from: rich  - 
Not sure how far you personally want to get into the diagnosis, but I think this might help.
Yep, that was the first thing that popped up when I looked into P0351.  Were the coil access that easy, I’d be tempted to try, but give my skill set, I feel I’d do more harm than good, too much in the middle of nowhere to attempt.

Thanks!
Dave

2017 TK
 
Re: P0351, likely bad coil
Reply #12 –
Quote from: RonB  - 
Hi Dave, on your old problem of random cylinder misfires one poster thought it might be fuel filter related.
The folks in Albuquerque tested the fuel pressure and volume, both were just fine, didn’t explain the misfires.

Dave

2017 TK