429 backfire issues
Thread Starter
|
New User
Joined: Sep 2015
Posts: 3
Likes: 0
429 backfire issues
I just built a drill rig onto a 1995 F-700 4x4 with a 7.0 L gas engine, fuel injected, has a govener on it. Use to be an Oregon Dept. Of Forestry vehicle , was well maintained, low mileage (98,000). My problem is the truck backfires loudly when use ing the gears to slow down going down hills, otherwise when accelerating it runs fine. Just changed the plugs,wires, cap & rotor, and have recently changed the EGR valve. The truck has all the smog stuff on it, it's California smog compliant.
Super Moderator
Joined: Apr 2004
Posts: 34,499
Likes: 2,811
Generic answer:
https://answers.yahoo.com/question/i...2173543AAkyKL2
You are getting unburned air/fuel past the exhaust valves when you run high rpms with the throttle closed. Could be a leaky injector, or a weak plug or wrong throttle setting. (WAGS all I admit)
Does this thing have OBD II? Or OBD I? Pulling codes might show something.
This will lead you into an endless series of fuel injection videos:
https://answers.yahoo.com/question/i...2173543AAkyKL2
You are getting unburned air/fuel past the exhaust valves when you run high rpms with the throttle closed. Could be a leaky injector, or a weak plug or wrong throttle setting. (WAGS all I admit)
Does this thing have OBD II? Or OBD I? Pulling codes might show something.
This will lead you into an endless series of fuel injection videos:
Thread
Thread Starter
Forum
Replies
Last Post
cbizzme
1968-Present E-Series Van/Cutaway/Chassis
10
May 5, 2018 01:47 AM
bmayden
Small Block V8 (221, 260, 289, 5.0/302, 5.8/351W)
2
Nov 1, 2012 08:27 AM
coldnorthpole
Ford Inline Six, 200, 250, 4.9L / 300
4
Aug 24, 2006 09:56 PM
