Diagnosing a dead cylinder
Forums at Modded Mustangs
Home Register FAQ Members List Calendar Timeslips Blogs Garage Gallery Auto Loans Search Today's Posts Mark Forums Read Auto Escrow


Go Back   Forums at Modded Mustangs > Mustang Forums > Modular Mustangs > 2005 - 2010

ModdedMustangs.com is the premier Ford Mustang Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools
Old July 24th, 2010, 07:06 AM   #1
Regular
 
dysan's Avatar
 
2005 Mustang GT
 
Join Date: Dec 2009
Location: Williamstown, NJ
Posts: 360
dysan has a spectacular aura aboutdysan has a spectacular aura about
iTrader: 0 reviews
Exclamation

Diagnosing a dead cylinder


I was driving my stang last night and then all of a sudden I felt a cylinder go out, change in sound on the engine and could feel that vibration. So I get back home and start pulling the COP connectors and figured out it's the 2nd cylinder back on the driver's side, I believe that's cylinder 6? When I pulled that COP plug there's no change in the engine, so I tried swapping the COP with another one and the same cylinder stayed dead. I also compared resistance of the spark plug from top to tip and that's the same as another so I don't think it's a plug either.

I looked in the online service manual at the wiring but I don't know how to figure out which PCM plug the COP wire I need to trace goes into. On the schematic it's got a number 15 at the PCM side and along the wire there's number 1025. Ford Service Manuals - Wiring Diagrams

Does anyone know which connector the wire is in? Top, middle or bottom? I guess I should also check the wires for the fuel injector since no fuel would most likely cause the same issue.

Thanks for any help you guys can provide. I need to get this figured out this weekend so I can install the supercharger next weekend.

__________________
300 stroker, 11:1, 7L2E iron block, 3.73's, MT ET Street Pro's. UPR solid LCA's, JPC race UCA. Kooks 1 3/4" LT's with 3" O/R H. 9.988 @ 136.55mph, E-Force with 3" pulley running E85. Tuned by Manuel from TUDYNO.
  Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old July 24th, 2010, 08:49 AM   #2
Resident Brewer
 
 
Join Date: Feb 2009
Location: Northern Harford County Maryland
Posts: 1,855
Anthony05GT is a jewel in the roughAnthony05GT is a jewel in the roughAnthony05GT is a jewel in the roughAnthony05GT is a jewel in the rough
iTrader: 1 reviews
Default

You need to do a compression test first. If you find a dead cylinder remove that side valve cover and inspect for a valvetrain issue. I'd do this before starting the engine again. If you have no obvious valvetrain issue, but a dead cylinder, sadly, the engine will probably have to be removed or at least pull that side's head for inspection.
__________________
JDM 302 Stroker, Whipple 10 rib 12 psi, L&M, JBA, J&M, LFP, Corsa, Stage II cams, Manley, MGW, McLeod RST, Eaton Posi, 3.73's, Metco, Steeda, Autometer, CDC, Street Scene, SOS, Tuned at JPC Racing by Kevin MacDonald
  Reply With Quote Quick reply to this message
Old July 24th, 2010, 02:55 PM   #3
Regular
 
dysan's Avatar
 
2005 Mustang GT
 
Join Date: Dec 2009
Location: Williamstown, NJ
Posts: 360
dysan has a spectacular aura aboutdysan has a spectacular aura about
iTrader: 0 reviews
Default

The odd thing is that it happened just like a switch was flicked. I finally go a code and it was a coil code. The weird thing is that the code says coil F which would be cylinder 5 but the one that's not functioning is cylinder 6. I confirmed that the correct wires are going to the correct coils so it's quite odd.

I'll be stopping by a guys shop tomorrow and we'll pull the cover as well as put a scope down the spark plug hole.
__________________
300 stroker, 11:1, 7L2E iron block, 3.73's, MT ET Street Pro's. UPR solid LCA's, JPC race UCA. Kooks 1 3/4" LT's with 3" O/R H. 9.988 @ 136.55mph, E-Force with 3" pulley running E85. Tuned by Manuel from TUDYNO.
  Reply With Quote Quick reply to this message
Old July 25th, 2010, 06:22 AM   #4
Regular
 
dysan's Avatar
 
2005 Mustang GT
 
Join Date: Dec 2009
Location: Williamstown, NJ
Posts: 360
dysan has a spectacular aura aboutdysan has a spectacular aura about
iTrader: 0 reviews
Default

Well, it was one of 2 things. I picked up a new spark plug and at the same time took the boot off the COP and cleaned the old grease and dirt from it as well as cleaned the spring real well. The combination of those 2 things fixed the issue.

I think there was too much dielectric grease in there causing an issue but I'll never know since I did both at once. Next weekend when I start the install of my E-Force I'll clean out all the COP's when changing to HT0 plugs that way it's all nice and fresh.

Thanks for the reply.
__________________
300 stroker, 11:1, 7L2E iron block, 3.73's, MT ET Street Pro's. UPR solid LCA's, JPC race UCA. Kooks 1 3/4" LT's with 3" O/R H. 9.988 @ 136.55mph, E-Force with 3" pulley running E85. Tuned by Manuel from TUDYNO.
  Reply With Quote Quick reply to this message
Old July 25th, 2010, 08:31 AM   #5
Resident Brewer
 
 
Join Date: Feb 2009
Location: Northern Harford County Maryland
Posts: 1,855
Anthony05GT is a jewel in the roughAnthony05GT is a jewel in the roughAnthony05GT is a jewel in the roughAnthony05GT is a jewel in the rough
iTrader: 1 reviews
Default

That was easy. I guess you're relieved.
__________________
JDM 302 Stroker, Whipple 10 rib 12 psi, L&M, JBA, J&M, LFP, Corsa, Stage II cams, Manley, MGW, McLeod RST, Eaton Posi, 3.73's, Metco, Steeda, Autometer, CDC, Street Scene, SOS, Tuned at JPC Racing by Kevin MacDonald
  Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Forums at Modded Mustangs forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools


Threads Similar to: Diagnosing a dead cylinder
Thread Thread Starter Forum Replies Last Post
one cylinder is dead why???!!? Street_Racer 2.3 Mustangs 6 March 6th, 2008 06:23 PM
dead cylinder KEIT01 5.0 Mustangs 8 March 4th, 2008 07:52 PM
need help diagnosing sonicblue 5.0 Mustangs 18 October 23rd, 2007 10:02 PM
95 5.0 Dead Cylinder behrwang 94-95 2 March 22nd, 2007 10:35 PM
dead cylinder 2001bullitt 99 - 04 14 January 14th, 2007 03:28 PM



All times are GMT -4. The time now is 06:18 PM.
Modded Mustangs is ©2005-2008, All Rights Reserved, And is Not Affiliated with Ford Motor Company.
Forum is powered by vBulletin ©2000 - 2014, Jelsoft Ent. Ltd. & SEO by vBSEO 3.3.2 ©2009, Crawlability, Inc.

powered by vBulletin ©2000 - 2014, Jelsoft Ent. Ltd.