eng. missing under coast condition?
Thread Starter
|
Senior User
Joined: Aug 2007
Posts: 110
Likes: 0
eng. missing under coast condition?
i have yet another question regarding my 85 dually i picked up. it seems that when you are doing about 55 or so and let off the fuel i am getting what appears to be a bad engine miss. any ideas?
Thread Starter
|
Senior User
Joined: Aug 2007
Posts: 110
Likes: 0
no it hasnt stalled out on me at idle, and i am pretty sure it is the motor missing because it does it sparadically. the whole truck bucks pretty bad when it does it. when you give it fuel again after it starts doing it,it goes away
Lead Driver
Joined: Jan 2005
Posts: 7,782
Likes: 221
From: Huntington Indiana
Going back to basics.. When was the last fuel filter change? have you changed the fuel return lines between the injectors? Wondering if some air is getting in when you let off on the power band. I also found on my 93 a bad fuel line from the tank along the frame. gave me real fits to find it. It ran rough like yours.
Thread Starter
|
Senior User
Joined: Aug 2007
Posts: 110
Likes: 0
i havent really noticed to much smoke, it does smoke a little whe you get on the throttle. the fuel filter looks new, i havent noticed the injector caps leaking any fuel but that doest mean they arent leaking fuel i guess. it doest have any cold start issues.
Trending Topics
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
One more question, does the truck try to stall if you rev the engine up to 1500-2000 RPM and then release the accelerator (at standstill in neutral)?
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
This is one I haven't heard before. A misfire should cause a smoke puff that lines up with the thump in the engine (or at least SHOULD). I would check the drive shaft just to be sure. A loose U joint can cause some strange symptoms (tranny in neutral).
Posting Guru
Joined: Sep 2007
Posts: 2,207
Likes: 1
From: Las vegas
Sounds like a bad ring in pinion to me. One of the teeth may be damaged on the back side when you let off the go pedal the oposit side of the ring and pinion ride on each other the bucking may be the bad tooth comming around.
Thread Starter
|
Senior User
Joined: Aug 2007
Posts: 110
Likes: 0
a chipped tooth in the ring and pinion would almost definately make some gear noise wouldnt it? a loose u joint would result in drive train clunk wouldnt it? i am getting neither of these. i am pretty sure it is the motor missing. its acting just like a gasser does when it is loading up with fuel. the truck is bucking pretty bad, and it doesnt make any clunking noise when it does it, which is sparadic.