5.0L (1979-1995) MustangTechnical discussions on 5.0 Liter Mustangs within. This does not include the 5.0 from the 2011 Mustang GT. That information is in the 2005-1011 section.
Sponsored by Weld Racing
Welcome to Mustang Forums!
Welcome to Mustang Forums.
You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!
Question from a friend:
My '86 Mustang GT is missing at high RPM. It starts missing at about 3500-4000rpm & it keeps getting worse. It won't rev over 5000rpm anymore.
It all started at one instant, not a gradual thing. I had got on it a few times earlier that night with no problems, it pulled strong all the way to 6500rpm. The first time it did it was when I was leaving a stop sign I was at full throttle & it wouldn't burn out, it usually smokes the tires easily all through first. It was making a sound like it had a big load on it, like the way it sounds when you try to climb a hill @ full throttle in 5th gear. It also sounded like it was backfiring alot.
Edit: it will rev to 7000 when in neutral
This ad is not displayed to registered or logged-in members. Register your free account today and become a member on Mustang Forums!
Forced Induction & Engine Management Systems
yeah, could be the timing... Or, something in the firing. Check everything that has to do with firing. Make sure you don't have a plug wire or two laying against a header. Also, check out the coil wire to see if it may be grounding on something. Maybe even as simple as a rotor button inside the distributor. Check all this and get back, Jason
Jason Hogan (870)-483-3338
93 notchback supercharged
85 monte carlo w/ blown 502
67 Chevy II 406 w/ nitrous
I had the same thing in my 86' GT. I had stock wires resting on the headers that were worn thin a little bit.. Then I was working in the garage with dim light and could see it arc a little bit.. bought new MSD wires and coil. made sure they weren't touching headers. Night and day difference.
69Mach1 - warmed up 395W (AFR 185s) and broken POS Gforce T5 with hydraulic clutch, 3.5" Alum DS, 3.50:1 posi, rack&pinion/tilt, 235/50ZR17x8 front & 285/40ZR18x9 rear, American Racing Nova wheels, all MSD, Holley 750, custom paint, headlight relays, Shelby drop & 2" lower all around, Hotwheels Redline scale is 1 to 1. http://photobucket.com/albums/v618/danaranda/69stang
This forum is owned and operated by Internet Brands, Inc., a Delaware
corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford
Motor Company or its related companies in any way. Ford® is a registered trademark of the Ford Motor