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  • 2005 - 2014 S-197 Mustang -General/Talk-

Misfire after pulling spark plugs?

  • Thread starter Thread starter nazzy
  • Start date Start date May 23, 2011
N

nazzy

New Member
May 22, 2011
2
0
0
May 23, 2011
#1
  • May 23, 2011
  • #1
The other day I pulled the spark plug on cylinder two on my 06 gt just to do a routine check up (I was having no problems beforehand) and after putting the plug back in noticed the idle seemed rough. I had accidentally dropped the plug before I put it back in, but didn't notice any cracks or signs of damage from the fall. I drove around for a bit, came home and let the car sit then left for work a few hours later and noticed the check engine light was coming on with a P0302 code (cylinder two misfire). The plug had looked a bit beat up but was running fine beforehand, connections were fine, and the coil must have been fine as well.

A few hours ago I had a friend come over to see if he could help me out, and we decided to pull the plug on cylinder 1 to compare as he was convinced the gapping on the plug on cylinder two was wrong. Make a long story short, we couldn't get the plug out on cylinder one and I didn't want to force it too much with all the horror stories floating around of spark plugs breaking in half and getting stuck within the block.

We fired the car back up after putting everything back, and now I'm getting a CEL with P0301 (misfire on cylinder 1) P0300 (random misfire, I'm assuming this is actually from cylinder two but the computer is picking it up as random as the misfire is now coming from two cylinders) and P0000.

We both concluded it must be something with the connection between the coil on the plug as everything was running fine beforehand and we never pulled the plug on cylinder 1. So we messed around with the coils for a bit and got nowhere. We're going to give it another go tomorrow to see if we can figure something out, but until then does anyone have any idea what this could possibly be?
 

jaybertx

Member
Apr 18, 2003
387
1
18
Sarasota, FL
May 23, 2011
#2
  • May 23, 2011
  • #2
Maybe put a dab of dialectric grease on the backside of the plug?
 

streethorse

15 Year Member
Oct 8, 2005
1,042
6
58
Dallas Texas
May 23, 2011
#3
  • May 23, 2011
  • #3
You say plug looked beat up. You have no choice but to go ahead
and change all plugs, check the cop's and boots carefully. If a plug breaks
you may need to get the specialty tool to get them out.
I fear this procedure myself but am only ay 45k. Good luck.
 

arcwcb

Member
Oct 26, 2009
417
2
19
Pennsylvania
May 23, 2011
#4
  • May 23, 2011
  • #4
Don't worry too much about changing the plugs, I did mine and as long as you take your time and shoot some seafoam on them to break down the carbon, they come out super easy. It's not that bad, I promise! lol
 

StreetsideStig

Active Member
Feb 22, 2011
1,012
48
48
May 23, 2011
#5
  • May 23, 2011
  • #5
I'd go with the gapping problem.

 
N

nazzy

New Member
May 22, 2011
2
0
0
May 24, 2011
#6
  • May 24, 2011
  • #6
Just for an update, me and my buddy took the coilpacks out of 1 and 2 and ran a test wire between the coilpack and the plug for both with the engine running, both times we had a connection. The engine actually seemed to be running better too...which leads me to believe for some reason the coilpack and the plug arent getting the proper connection within the block. Could gapping still be an issue if we had a solid connection with the test wire?
 
T

thunderstang618

New Member
May 17, 2011
6
0
0
san diego california
May 29, 2011
#7
  • May 29, 2011
  • #7
chances are ur better off just replacing ur spark plugs like others have said i am having the same problem in my 05 right now i just havnt did the code reading but sometimes with the stang coils they get messed up from pulling them out ur just better off to buy new plugs an coils as for gaping if u go to auto zone they have sparkplugs u dont have to gap they just go right in perfect plus their also pretty high performance but a bit spendy just a suggestion good luck
 
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