The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

Engine misfire

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

My 2012 Boss has started intermittently misfiring between 2000 and 3000 rpm, especially when it is cold. Also am noticing some light noise that sounds like valve train between the same rpm range, but only when it is cold. After the engine warms up, the noise dissapears.
Haven't been back to Frod yet. Anyone having any similar problems, or any ideas that might shed some light on what is happening would be appreciated.
 
I have not but I have noticed mine load-up after running it hard then then turning it off. When I start it back up minutes later it will not run smooth. I've experienced this 3-4 times now.
 
Thanks for the reply. I talked to my salesman today, who is a personal friend also. I'm taking it back on this Friday to let them take a look at it. After I hear from them I'll post what I find out.
The only things I have done to it is that I have removed the baffles in the side pipes & put a Rousch axle back system on it. Otherwise it is as it left the factory.
 
548
0
Did your check engine light come on after the misfires? My problem was a bad wiring harness, but since that has been replaced I haven't had any issues to date.
 
stumpy said:
My 2012 Boss has started intermittently misfiring between 2000 and 3000 rpm, especially when it is cold. Also am noticing some light noise that sounds like valve train between the same rpm range, but only when it is cold. After the engine warms up, the noise dissapears.
Haven't been back to Frod yet. Anyone having any similar problems, or any ideas that might shed some light on what is happening would be appreciated.

Are you sure it is a misfire? Has it thrown a code? There seems to be a little "trailer hitching" effect that happens when the engine is cold in that rpm range. The problem becomes more pronounced if the AC is on. Lets us know what the dealer saids.
 

TMO Supporting Vendors

Buy TMO Apparel

Buy TMO Apparel
Top