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reader code PO358

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Old Jul 2, 2017 | 04:51 PM
  #1  
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reader code PO358

I have a 1999 Motor home has a 6.8L Triton V-10 just had a 100,000 milie tune up to include 10 new titanium spark plugs 3 months later I have this problem While driving the other day I had no power to take small hills. Little neighborhood hills were slowing me to 10 mph. Hoping its was the MAF sensor although it didn't throw a code when it was doing this but a code for PO358. So what's next back to the Ford Dealership for repairs?
 
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Old Jul 2, 2017 | 09:07 PM
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A P0358 DTC indicates a fault was detected with the #8 COP primary circuit.

Check for a broken, loose or damaged COP connector first.

I have titanium (and plastic) joints but I've never seen a titanium spark plug.
 
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Old Jul 2, 2017 | 09:12 PM
  #3  
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Originally Posted by projectSHO89
A P0358 DTC indicates a fault was detected with the #8 COP primary circuit.

Check for a broken, loose or damaged COP connector first.

I have titanium (and plastic) joints but I've never seen a titanium spark plug.
where is the COP connector located for the # 8 will this require the Ford Dealership to fix?
 
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Old Jul 2, 2017 | 11:07 PM
  #4  
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Originally Posted by Rhodi
where is the COP connector located for the # 8
On the #8 coil.
Middle cylinder left side of vehicle.
Originally Posted by Rhodi
will this require the Ford Dealership to fix?
It will if you can't find the #8 coil.
Most people will swap in a new coil pigtail if that is the issue.
If you are unable to splice wires then take it to someone who can.

What may possibly have happened,
when the spark plugs are removed, the coil electrical connector for each cylinder needs to be unplugged. Sometimes when they get unplugged, the latch that keeps it connected can break off and then after reassembly the connector can then randomly slide off due to engine and road vibration.
 
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Old Jul 3, 2017 | 12:14 PM
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Well The ford dealer showed where to find the number 8 coil, there no way I can even get to it, maybe thats why they get the big bucks to replace them, there is too much stuff in the way even for me to get at it, no wonder most mech's don't like working on these V-10's that are in the Motorhomes So my only option is to have the dealer fix the problem. Thank you



Originally Posted by Sam I Am
On the #8 coil.
Middle cylinder left side of vehicle.
It will if you can't find the #8 coil.
Most people will swap in a new coil pigtail if that is the issue.
If you are unable to splice wires then take it to someone who can.

What may possibly have happened,
when the spark plugs are removed, the coil electrical connector for each cylinder needs to be unplugged. Sometimes when they get unplugged, the latch that keeps it connected can break off and then after reassembly the connector can then randomly slide off due to engine and road vibration.
 
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Old Jul 7, 2017 | 07:16 AM
  #6  
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Ok I took my 1999 Motor home to the Ford Dealer and after 4 hours they have found the problem, It was the PCM board that is bad. They call it the left bank that tell the 1,2,3,4,5 cyl. what to do. They also told me that this PCM is obsolete and they don't make these any more for this year. So after another hour they found one new one on the internet from a ford dealership back East. to the cost of $510 dollars. So I said I see allot of these for sale on the internet for the F-450 Super Duty V-10 engine, but they also said that they would not work not compatible because of the year of F-450 that I have. I find that hard to believe but could be true. well any ideals anyone has please pass them along I hate to see the right side go out out on me during the road trip.
 
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