2005-2009 Mustang Information on The S197 {Gen1}
Sponsored by:
Sponsored by:

08 GT misfire...HELP!

Thread Tools
 
Search this Thread
 
Old 8/9/17, 12:57 PM
  #1  
Member
Thread Starter
 
mike08GT's Avatar
 
Join Date: August 9, 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
08 GT misfire...HELP!

On a trip to MN I needed gas but couldn't get 93 octane so I put in 87 and some octane boost. It's pretty stock. SCT 93 tune, throttle body spacer. Just recently did plugs and coils. It had been running strong til this trip and now it misfires. Only does it when I step on it and its pulling a little and then it misfires...let up on the gas and it straightens out. Lower rpm's it has the power but above 2500-3000 it starts up again. Today I put a new crankshaft sensor and cleaned the MAS. I'm not sure where to go from here.

Thanks
Mike
Old 8/10/17, 09:22 PM
  #2  
Legacy TMS Member
 
Gabe's Avatar
 
Join Date: August 7, 2011
Location: NC
Posts: 5,265
Received 537 Likes on 420 Posts
What brand plugs and coils did you put in?
Old 8/11/17, 04:28 PM
  #3  
Member
Thread Starter
 
mike08GT's Avatar
 
Join Date: August 9, 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
motorcraft
Old 8/22/17, 09:26 PM
  #4  
Member
Thread Starter
 
mike08GT's Avatar
 
Join Date: August 9, 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
well after a week in the ford shop and $731 it was the spark plugs!... before I sent it to the shop I returned to stock tune...now I got the car home and installed a JLT CAI and went to tune it again and the SCT says its not married to my car and it won't let me do anything. and of course the car wouldn't run at all. where do I go from here?
Old 8/23/17, 04:13 PM
  #5  
Legacy TMS Member
 
Gabe's Avatar
 
Join Date: August 7, 2011
Location: NC
Posts: 5,265
Received 537 Likes on 420 Posts
Probably need to contact SCT.

The spark plugs causing the issue, were they Motorcraft?
Old 8/23/17, 05:09 PM
  #6  
Member
Thread Starter
 
mike08GT's Avatar
 
Join Date: August 9, 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
yes they were motorcraft but he said they weren't quite the right ones
Old 8/26/17, 08:45 AM
  #7  
Mach 1 Member
 
07 Boss's Avatar
 
Join Date: August 1, 2015
Posts: 511
Likes: 0
Received 51 Likes on 47 Posts
Originally Posted by mike08GT
yes they were motorcraft but he said they weren't quite the right ones
???? What do you mean by they weren't the right ones? Did you change the plugs before this misfire started happening?
Old 8/27/17, 04:39 PM
  #8  
Member
Thread Starter
 
mike08GT's Avatar
 
Join Date: August 9, 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Plugs

Yes I did change plugs and coils about 30 days before the misfire. I can't remember the plug number but they were motorcraft with the diodes enclosed. They replace them with the standard plug design. It ran strong after I changed plugs. I also just read that the anti-sieze grease has been fouling out plugs. Some how it gets down to the tips. Anyway it's running great now.
Old 8/27/17, 04:41 PM
  #9  
Member
Thread Starter
 
mike08GT's Avatar
 
Join Date: August 9, 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
SCT

Also hot my ACT straightened out and will reinstall the JLT CAN I on Tuesday




All times are GMT -6. The time now is 04:15 PM.