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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

ODBii code P0356

  • Thread starter Thread starter pkwest
  • Start date Start date Apr 18, 2007
P

pkwest

New Member
Apr 18, 2007
4
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1
Apr 18, 2007
#1
  • Apr 18, 2007
  • #1
I just installed my new engine. It ran great for a short time after which it started to miss. I checked compression and it is really consistent. I changed the plugs thinking I may have damaged one while it was in the box of misc parts. It ran great for about 15 minutes then it started missing again. I thought P0356 was referring to COP for #5 so I
swapped #5 & #6. I still got the same code P0356. Which COP is F. I did get a bit sloppy with the anti seize when I installed the previous plugs. It was on
the porcelain of the plugs when I pulled them. Is anti seize a conductor? Could that have caused a COP to fail? The ford service dvd says erroneous ignition and etc related dtc's may be due to salt water intrusion into the CKP harness connector. So I cleaned the connector at the CKP sensor. No change.
 

4.6andSlicks

New Member
Aug 22, 2006
171
1
0
Central Connecticut
Apr 18, 2007
#2
  • Apr 18, 2007
  • #2
*Open coil driver circuit in harness
*Coil driver circuit shorted to ground
*Damaged coil
*Damaged PCM
*Coil driver circuit shorted to 12v

Sounds like it's on the coil side. All the moving around could have broken a wire inside the insulation. When you change a plug or move it, it makes connection for 15 seconds or so. Above is from the manual.
 
D

Dragstr05

New Member
Dec 21, 2004
643
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Stafford VA
Apr 18, 2007
#3
  • Apr 18, 2007
  • #3
^^ Agreed.

If you swapped coils coils and got the same code for the same cylinder, its in the harness/connector.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 18, 2007
#4
  • Apr 18, 2007
  • #4
That code is for cylinder #6 so it's the second plug from the front on the drivers side.

After you swap it with another coil make sure you clear the codes then retest, if you did not clear the code the pcm will still have the code in there for cyl #6 coil and may have not had time to set the code for the cyl you changed it too.

Most likely the problem is the coil itself. It is very very rare to have a PCM driver fault or even a wiring fault.

If you want to check for wiring problems check for continuity from pin #1 of the PCM to pin number 2 of the connector on coil #6

Also check for power at pin #1 of the coil connector
 
P

pkwest

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Apr 18, 2007
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Apr 18, 2007
#5
  • Apr 18, 2007
  • #5
Thanks for all the suggestions. I will be getting into this in the next two days. below is a quote my ford service dvd.
" Note: On certain applications with Electronic Throttle Control (ETC), erroneous ignition and ETC related DTC's may be set due to salt water intrusion into the CKP harness connector. These DTC's are: P0320, P0351, P0356 and P2106. Thoroughly clean the connector, pack with di-electric grease and retest. If the problem returns, REPLACE the CKP sensor."
Could I have a bad CKP sensor???
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 18, 2007
#6
  • Apr 18, 2007
  • #6
pkwest said:
Thanks for all the suggestions. I will be getting into this in the next two days. below is a quote my ford service dvd.
" Note: On certain applications with Electronic Throttle Control (ETC), erroneous ignition and ETC related DTC's may be set due to salt water intrusion into the CKP harness connector. These DTC's are: P0320, P0351, P0356 and P2106. Thoroughly clean the connector, pack with di-electric grease and retest. If the problem returns, REPLACE the CKP sensor."
Could I have a bad CKP sensor???
Click to expand...

When a CKP sensor goes bad normally the car will not start. Plus your car does not have electronic throttle control.

What manual is that out of and what section page numbers so I can read it.
 
P

pkwest

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Apr 18, 2007
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Apr 19, 2007
#7
  • Apr 19, 2007
  • #7
Thanks again. Here is where I read it.

The ford service DVD 2002-2004 January 2005. Powertrain control / emissions diagnosis. 2004 mustang - 2004 PCED On Board Diagnostics SECTION 5: Pinpoint Tests Procedure revision date: 05/23/2004
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 19, 2007
#8
  • Apr 19, 2007
  • #8
pkwest said:
Thanks again. Here is where I read it.

The ford service DVD 2002-2004 January 2005. Powertrain control / emissions diagnosis. 2004 mustang - 2004 PCED On Board Diagnostics SECTION 5: Pinpoint Tests Procedure revision date: 05/23/2004
Click to expand...

I will look into that latter since I will have to skim the entire section. But I would check that out since it's easy to take a look at the connector and clean it.
 
P

pkwest

New Member
Apr 18, 2007
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1
Apr 20, 2007
#9
  • Apr 20, 2007
  • #9
It was the wire from the pcm to the coil. It was broken about 5 inches from the coil. The first time I measured it the wire had continuity. When I rechecked it last night I wiggled the wire and it showed up. It runs great now. Thank for all the help.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 20, 2007
#10
  • Apr 20, 2007
  • #10
pkwest said:
It was the wire from the pcm to the coil. It was broken about 5 inches from the coil. The first time I measured it the wire had continuity. When I rechecked it last night I wiggled the wire and it showed up. It runs great now. Thank for all the help.
Click to expand...

cool glad you got it
 

4.6andSlicks

New Member
Aug 22, 2006
171
1
0
Central Connecticut
Apr 20, 2007
#11
  • Apr 20, 2007
  • #11
pkwest said:
It was the wire from the pcm to the coil. It was broken about 5 inches from the coil. The first time I measured it the wire had continuity. When I rechecked it last night I wiggled the wire and it showed up. It runs great now. Thank for all the help.
Click to expand...

Great when a plan comes together. Number one on the list. Those Ford manuals do come in handy.

*Open coil drive circuit in harness
 
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