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  • SN95 4.6L Mustang Tech

Check Engine Light

  • Thread starter Thread starter na2slow2
  • Start date Start date May 21, 2010
N

na2slow2

New Member
May 13, 2009
6
0
0
May 21, 2010
#1
  • May 21, 2010
  • #1
When I started my car up this afternoon it was hard to start. When it finally started it felt like it was down a few cylinders. On my drive home it had no power and shook really bad. When I ran the codes after limping home I got 5 codes p0354,55,56,58,and p0306. A misfire on 6 and 4 ignition coil circuit malfunctions. Dont make much sense to me. Has anyone ever had this problem or know of any possible place to start hunting. The brakes were gonna recieve some attention this afternoon, guess not now. Thanks Kevin

99GT
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
May 21, 2010
#2
  • May 21, 2010
  • #2
Check COP connector C1045

COP 4,5,6, and 8 all share the same connector (C1045). C1045 is located "engine compartment, RH side rear".

COP 1,2,3, and 7 pass through connector C133.

Has any recent work been done? Pressure washed the engine bay?

In any case, check the engine harness connectors. Look for loose connections.
 
N

na2slow2

New Member
May 13, 2009
6
0
0
May 21, 2010
#3
  • May 21, 2010
  • #3
Thanks, I will give that a look in the morning before I go to work. I put a clutch in it a couple mounths ago. I took the low pressure switch connector off on the ac, and charged it. Thats about all of the work done lately. Thanks again Kevin
 
N

na2slow2

New Member
May 13, 2009
6
0
0
May 22, 2010
#4
  • May 22, 2010
  • #4
Update

Checked for that connector, all of my coil wires go into one huge harness, then both banks have a ground on the front of the engine. I erased all of the codes, went on a test drive came back with only one code 306 misfire code. Curious if maybe one coil went bad and is messing up the rest of the system. Thanks Kevin
 

joshjwc9

Active Member
Jun 12, 2006
1,095
17
39
Palm Harbor, FL
May 22, 2010
#5
  • May 22, 2010
  • #5
How old or new is the battery? How do the connections looks? Make sure they are tight and the battery isnt dying if it is over like 4 or 5 years old. Make sure terminals are tight like I said.

Have you recently had any issues with the car starting and the gauges pegging then returning to normal? That would mean a weak battery/charging system.

Your issue could have been caused by a bad coil yes, but I would suggest swapping it from cylinder to cylinder and see if the code follows the coilpack. Apparently the coil could be grounding itself to the block if there was a tear in the boot or something like that (I have actually had a torn boot do this and give a p0352 code, causing me to pull every plug and COP, checking each one in the process, finding 1 that was grounding and replaced the boot and all was good after that.)

Good Luck!
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
May 22, 2010
#6
  • May 22, 2010
  • #6
For the 1999-2000 MY, the connector number is C1007. It is a medium sized 13 pin square connector. On my 2000 it is located between the main engine connector and the firewall. It is almost touching the large main engine connector.

If you are down to just a misfire on a single cylinder, start by swapping the COP with another cylinder and see if the code follows the COP.

Also, check the spark plugs wells for moisture. Consider blowing out all of the wells as the 4.6 is bad about retaining moisture in the spark plug wells.

Note, if a moisture induced misfire is allowed to continue, this can damage the COP boot insulation. It is possble to buy just the replacement boot. Much cheaper than the entire COP.
 
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