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1999 Cobra plugs

  • Thread starter Thread starter 1999redcobra
  • Start date Start date Aug 21, 2007
1

1999redcobra

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Jul 11, 2007
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Aug 21, 2007
#1
  • Aug 21, 2007
  • #1
Ok so I have a cylinder 5 misfire so I need new plugs im guessing. So i was thinking of getting NGK irridium so I looked on ebay and this is all i could find.

http://cgi.ebay.com/ebaymotors/03-04-FORD-MUSTANG-COBRA-NGK-IRIDIUM-IX-SPARK-PLUGS_W0QQcmdZViewItemQQcategoryZ33693QQihZ017QQitemZ270155846238QQrdZ1QQsspagenameZWDVW

I dont know they say they are for 03-04 cobras would they work on my 99 or what and where should i go to find good plugs?
 

COBRA90GT

Mustang Master
Sep 22, 2001
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Aug 22, 2007
#2
  • Aug 22, 2007
  • #2
It's probably more likely that your misfire is the result of could be a faulty coil pack, not the sparkplug. When was the last time you changed the sparkplugs?
It would probably be a good idea to change the plugs (at least inspect them).

I'm personally not a fan of the fancy overpriced sparkplugs out there on the market. I'd rather spend my money on other mods. Nothing wrong with using a regular 'ol copper sparkplug. YMMV

G'luck with the misfire problem.
 
1

1999redcobra

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Aug 22, 2007
#3
  • Aug 22, 2007
  • #3
I dont know when the plugs where changed last I bought the car may of last year and the misfire light came on when the car was in storage this year i dont drive it that much so i havent done anything but now i just want to get it fixed
 
K

Kilgore Trout

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Mar 30, 2005
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Aug 22, 2007
#4
  • Aug 22, 2007
  • #4
The only brands I would consider are NGK or Motorcraft and I generally prefer copper but right now I am trying out a fine electrode platinum Motorcraft plug AGSF12-FM1 which is the plug Ford currently recommends for my car. It is two heat ranges colders than what you would probably consider. For you I would suggest copper NGKs stock n/a heat range gapped @.052
 
T

thomas91169

I'd donkey punch my sister.
Aug 19, 2005
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Modesto, CA
Aug 24, 2007
#5
  • Aug 24, 2007
  • #5
seeing youre a n/a cobra, id just get normal NGK's or Motorcrafts. No need to get all fancy like us termie guys and run iridiums.

btw please make sure you gap it right. DO NOT just assume theyre pre-gapped like the guy that had the car before me, theres a big difference between .044 that they come and the .032 that you need.
 
K

Kilgore Trout

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Aug 24, 2007
#6
  • Aug 24, 2007
  • #6
No way does a n/a car need to be gapped at .032 its more like .052-.054
 
1

1999redcobra

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Aug 24, 2007
#7
  • Aug 24, 2007
  • #7
Ok so now what does it need to be gapped and how do you gap them right
 

SVT32VDOHC

waiting for the next hack atta
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Aug 27, 2007
#8
  • Aug 27, 2007
  • #8
the smaller the gap, the more boost you have, so N/A guys, stick to what Ford suggests in the owners manual.
 
1

1999redcobra

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Sep 26, 2007
#9
  • Sep 26, 2007
  • #9
So what are the steps to changing the plugs in a 99
 

COBRA90GT

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Sep 22, 2001
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Sep 27, 2007
#10
  • Sep 27, 2007
  • #10
1999redcobra said:
So what are the steps to changing the plugs in a 99
Click to expand...


1 - Remove each sparkplug cover that sits atop each valve cover (two 8mm or 10mm bolts, I can't recall exactly).

2 - Unplug each COP from each sparkplug (be careful, do not damage the "boots" or COP itself).

3 - Use a long extension with a sparkplug socket to remove each sparkplug.


 
1

1999redcobra

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Sep 27, 2007
#11
  • Sep 27, 2007
  • #11
is it hard to get the COP off any speacial way
 

stangsalwayswin

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May 23, 2007
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Alexander Ar
Sep 28, 2007
#12
  • Sep 28, 2007
  • #12
I work at advance auto parts and I just put the NGK Iridium Tr55 plugs in my 99 cobra and they work great! And yes they are different than 03 04 cobra plugs just go to advance and get them for a 99 for about $6.96 ea.
 
1

1999redcobra

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#13
  • Sep 28, 2007
  • #13
But it was a pretty easy project though
 

SVT32VDOHC

waiting for the next hack atta
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Sep 28, 2007
#14
  • Sep 28, 2007
  • #14
Has there been issues with blowing the plugs out of the head on 4.6L Mustang engines?? I have people tell me they have that problem with 5.4L Econoline and Truck motors. Is that the case with the 4.6L too?

I want to change the plugs on this 72K 4.6L SOHC motor I am putting into my mod fox, but I am a little scared of doing so. The engine ran great in the car I pulled it out of.
 

WANNA_BE_GT

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Aug 5, 2000
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Seattle WA USA
Sep 28, 2007
#15
  • Sep 28, 2007
  • #15
SVT32VDOHC said:
Has there been issues with blowing the plugs out of the head on 4.6L Mustang engines?? I have people tell me they have that problem with 5.4L Econoline and Truck motors. Is that the case with the 4.6L too?

I want to change the plugs on this 72K 4.6L SOHC motor I am putting into my mod fox, but I am a little scared of doing so. The engine ran great in the car I pulled it out of.
Click to expand...

Yes, there has been issues with our motors because of the aluminum heads.

From my understanding, you don't want to run anything more than a copper plug on a boosted format. Mainly due to detonation issues and worries.
 
1

1999redcobra

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Jul 11, 2007
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Oct 4, 2007
#16
  • Oct 4, 2007
  • #16
I just got some Bosch ir fusion spark plugs and should i put some antisieze on the threads? Also those come pre gapped so i dont have to do anything to them except put them in right.
 
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