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p0355 - ignition experience then come in

  • Thread starter Thread starter ForgedBlack01gt
  • Start date Start date Sep 22, 2005
F

ForgedBlack01gt

Member
Nov 19, 2004
33
0
7
San Jose, Ca
Sep 22, 2005
#1
  • Sep 22, 2005
  • #1
My money pit of a car broke again ...... anyone thrown just P0355 Ignition Coil Primary circuit malfunction?

what do you think is wrong this time?

I have replaced almost everything now because my car only seems to make it a couple months before it breaks again. About 40,000 miles ago I tried to dyno my car and the wires where you read the rpms were shorting out and I took it to ford and they told me no problem there (at 8,000 miles ago I broke an exhaust valve and ever since installing the longblock with cams it stalls every now and again). Is this just a bad coil unrelated to the other problems or should I just replace the whole ignition system? What do I have to do to enjoy my car for at least a year without breaking it again?

This car is literally becoming a joke from its inability to run besides the fact that each time I replace something I pay for the best replacements. So now I have a brand new forged long block with cams that I do not want to even risk messing up. Are all of the factory parts complete SHlT?

All I have left that came on the car is the ignition/computer system, intake, alternator, fuel system and rear end. Everytime I get close to supercharging or messing with suspension something else goes wrong.
 
F

ForgedBlack01gt

Member
Nov 19, 2004
33
0
7
San Jose, Ca
Sep 22, 2005
#2
  • Sep 22, 2005
  • #2
Ford says $1500 to replace all the coil on plugs and the computer ........ I am thinking I will probably replace them myself since I have all the tools and alot of free time but I have no clue if this is possibly just the computer or the coil on plugs?
 

ToplessStang

Member
Mar 7, 2004
591
0
17
Montreal, Canada
Sep 22, 2005
#3
  • Sep 22, 2005
  • #3
ForgedBlack01gt said:
Ford says $1500 to replace all the coil on plugs and the computer ........ I am thinking I will probably replace them myself since I have all the tools and alot of free time but I have no clue if this is possibly just the computer or the coil on plugs?
Click to expand...


Ford should be able to tell you if it is just a coil, more than one coil or the PCM. I doubt all 8 coils went bad at one time. Is the car running rough as compared to before??? Was there any other code like a P030X
 
F

ForgedBlack01gt

Member
Nov 19, 2004
33
0
7
San Jose, Ca
Sep 22, 2005
#4
  • Sep 22, 2005
  • #4
Car ran almost like when I broke my exhaust valve I thought (felt like one cylinder doing nothing now that I think about it and with the cams you can feel when each cylinder fires almost) ..... going to buy a coil on plug and try to go through them one by one until no check engine light or I will replace them all then the computer I guess
 

forpit2000gt

Founding Member
Jun 30, 2002
2,490
0
0
Columbia, SC
Sep 22, 2005
#5
  • Sep 22, 2005
  • #5
A scanner should show which cylinder is missing if it is a COP. Sounds like a PCM problem. Does the car have a chip in it? Any tuning?
 
F

ForgedBlack01gt

Member
Nov 19, 2004
33
0
7
San Jose, Ca
Sep 22, 2005
#6
  • Sep 22, 2005
  • #6
I have a superchips Microtuner (handheld programmer but it doesn't let you modify the tune just shift points, pressure and gear ratio) I have been holding off on a tune for forced induction ....... it said P0355 Ignition Coil Primary circuit malfunction and nothing else ........ I returned the tune to stock before giving it over to ford and the same problem popped up after them driving it
 

ToplessStang

Member
Mar 7, 2004
591
0
17
Montreal, Canada
Sep 22, 2005
#7
  • Sep 22, 2005
  • #7
Ok again there is no way you have to replace all 8 COP's. I don't understand all the info on how your car is running now but assuming you feel the engine miss at idle, try disconnecting the electrical connector on just 1 coil as the engine is running. If the engine changes sound/runs worse, that is not the coil/cylinder with the problem so reconnect and move on to the next. Take note of which coil when disconnected has NO effect on the engine idle. This will narrow things down a bit. Doesn't mean it's not the PCM but it's a start on what it might be. If let's say you notice that unplugging coil #1 (passenger side coil at the front closest to the belt) has no effect on engine sound, switch it with coil #2 and retest. If there is no idle change with coil#2 once the switch was done, the COP is your problem. Hope this isn't to complicated .
 
F

ForgedBlack01gt

Member
Nov 19, 2004
33
0
7
San Jose, Ca
Sep 22, 2005
#8
  • Sep 22, 2005
  • #8
I have the problem of my car varies at idle too 500-1000 roughly....... I will definately give that a try though .... never heard of an engine blowing at idle
 
I

importstomper

New Member
Aug 5, 2004
9
0
0
Sep 23, 2005
#9
  • Sep 23, 2005
  • #9
well hopefully you haven't pulled the coils out and got them mixed up yet because a 355 error means that the coil on cylinder number 5 is malfunctioning. Mine is doing the same damn thing but on cylinder 4 po354 code
 
I

importstomper

New Member
Aug 5, 2004
9
0
0
Sep 23, 2005
#10
  • Sep 23, 2005
  • #10
hey
I am having same problem
going to replace coil again tomorrow morning and see what happens
 

ToplessStang

Member
Mar 7, 2004
591
0
17
Montreal, Canada
Sep 23, 2005
#11
  • Sep 23, 2005
  • #11
importstomper said:
well hopefully you haven't pulled the coils out and got them mixed up yet because a 355 error means that the coil on cylinder number 5 is malfunctioning. Mine is doing the same damn thing but on cylinder 4 po354 code
Click to expand...


Wrong, code P0305 is for cyl. #5 missfire.
 
F

ForgedBlack01gt

Member
Nov 19, 2004
33
0
7
San Jose, Ca
Sep 23, 2005
#12
  • Sep 23, 2005
  • #12
I took my car to JBA ..... They are going to dyno my car and check the air to fuel ratio after they fix it ...... They said that what ford said didn't sound right when I called them .... might put a computer chip in it finally if I ebay my tuner
 
I

importstomper

New Member
Aug 5, 2004
9
0
0
Sep 24, 2005
#13
  • Sep 24, 2005
  • #13
ToplessStang said:
Wrong, code P0305 is for cyl. #5 missfire.
Click to expand...

READ YOUR BOOK AGAIN 355 is #5 coil malfuntion.

PO355 Ignition coil no. 5 primary circuit fail STRAIGHT FROM THE DAMN BOOK
 

ToplessStang

Member
Mar 7, 2004
591
0
17
Montreal, Canada
Sep 24, 2005
#14
  • Sep 24, 2005
  • #14
importstomper said:
READ YOUR BOOK AGAIN 355 is #5 coil malfuntion.

PO355 Ignition coil no. 5 primary circuit fail STRAIGHT FROM THE DAMN BOOK
Click to expand...


First off DON'T YELL . P0355 doesn't mean coil #5 is bad. Yes it can be but it can also be caused by the PCM, Open coil driver circuit in harness and about 5 other things. By switching the way I explained, it will narrow it down to the root cause condidering he doesn't have the test equipment to test the coil. You can read your "book" all you want but hands on experience finds the problem .
 
I

importstomper

New Member
Aug 5, 2004
9
0
0
Sep 24, 2005
#15
  • Sep 24, 2005
  • #15
The book is crap anyway just like the cars, I was never happier when I first got my stang gt and all the piece of crap has been is a money pit, just like he said, I have never been so dissappointed in a ford product, I am looking for something to trade it off for right now. I haven't had 3 months of continuous good driving since I bought the car. The 91 caprice classic daily driver I had before it tooking a beating everyday and never had a sign of trouble for over 3 years and 130,000 miles. I am really dissapointed in FORD on this one.
 
F

ForgedBlack01gt

Member
Nov 19, 2004
33
0
7
San Jose, Ca
Sep 30, 2005
#16
  • Sep 30, 2005
  • #16
JBA says they are basically stumped. They said they tested the coil on plugs and they are all good but they said my car has no vacume so that is why it is running rough and that my TPS might be bad since it moves around alot..... they are stumped as to why my RPMs are shorting out on the dyno around 4,000 RPM then going back up ..... Thinking a dyno tune chip might fix at least the vacuum and hopefully the RPMs too?? Maybie it is a short on the harness???? Anyone got any ideas????
 
F

ForgedBlack01gt

Member
Nov 19, 2004
33
0
7
San Jose, Ca
Oct 7, 2005
#17
  • Oct 7, 2005
  • #17
in case someone searches for this code dyno tuned fixed everything ......... 250hp/368tq
 
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