slight bucking under light load
Posting Guru
Joined: Feb 2001
Posts: 1,514
Likes: 0
From: Maple Grove, PA
slight bucking under light load
New to the board but looks cool!!
when I am under a light load and barley on the gas peddle my truck begins to buck a little bit. I tried spark plug wires and it did nothing. I though the it could of been crossfire so I separated the number 7 and 8 cylinder wires but that did nothing also. Maybe injectors but I am confused now about what to try next.
thank you for the info
when I am under a light load and barley on the gas peddle my truck begins to buck a little bit. I tried spark plug wires and it did nothing. I though the it could of been crossfire so I separated the number 7 and 8 cylinder wires but that did nothing also. Maybe injectors but I am confused now about what to try next.
thank you for the info
Posting Guru
Joined: Apr 2000
Posts: 1,345
Likes: 0
From: NorCal
slight bucking under light load
Sounds familiar. For a little test (without knowing the year, model, or engine the truck other than it's a V-8) try removing the green vacuum line from the EGR valve and see if the bucking stops.
Senior User
Joined: Feb 2000
Posts: 175
Likes: 0
slight bucking under light load
I have the same problem with my EFI 300 and from other posts the problem can be rooted in some of these additional areas: MAP Sensor, Idle Air Bypass Valve(sometimes needs disassembly and cleaning), Sticking Throttle Plates(Manual cleaning with soft bristle brush),ECM(expensive piece to swap out)...Phillip Guidry, one of the senior members of this site, usually recommends a full manual cleaning of the ThrottleBody(IAC included). It is also important to reset the computer(disconnect battery for an hour) following this type of service.
WHaynes
93 F150 4.9L 4x4
4" ProComp StII Lift
BFG 33in 4.10's
Detroit TrueTrac's
WHaynes
93 F150 4.9L 4x4
4" ProComp StII Lift
BFG 33in 4.10's
Detroit TrueTrac's
Posting Guru
Joined: Sep 2000
Posts: 1,586
Likes: 0
From: Linwood, N.J. USA!
slight bucking under light load
How are the plugs, cap and rotor? How old is the coil? Did you replace the fuel filter? You may just need a complete tune-up. I would also check for vacuum leak. Good luck.
Jakegypsum // Ford fleet, soup to nuts.
Jakegypsum // Ford fleet, soup to nuts.
Fleet Mechanic
Joined: Aug 2000
Posts: 1,504
Likes: 1
From: Texas
slight bucking under light load
Had the same problem with the 300 that used to call my truck home. Mine after over $1,000 worth of new parts. (sensors, caps, plugs, wires, a new distributor, and this, that, and what not.) Turned out to be a plugged catalytic convertor! These stupid contraptions can cause you all the headaches in the world. And that $1,000 I spent was in 1 year. After that and replacing the convertors with a high flow unit, it ran fine. But still nothing like what I wanted, so out it came, and a V8 now calls my truck home.
1988 F-150, SWB, 5.0 EFI (formerly 4.9 EFI), M5OD 5 speed, 3.08 gears, Summit shorty truck headers, Custom built Flowmaster exhaust system. Force 4 LP6000 lightbar, Federal signal PA-300 100 watt siren, Icom IC-V100 50 watt mobile radio.
=======================================
1965 F-100 (just purchased 1/18/01), SWB, 390, C-6 auto. Dual exhaust, Not much else to do to it.
Can see both below.
[link:www.geocities.com/hotrodford_88/|Hotrodford_88's Webpage]
1988 F-150, SWB, 5.0 EFI (formerly 4.9 EFI), M5OD 5 speed, 3.08 gears, Summit shorty truck headers, Custom built Flowmaster exhaust system. Force 4 LP6000 lightbar, Federal signal PA-300 100 watt siren, Icom IC-V100 50 watt mobile radio.
=======================================
1965 F-100 (just purchased 1/18/01), SWB, 390, C-6 auto. Dual exhaust, Not much else to do to it.
Can see both below.
[link:www.geocities.com/hotrodford_88/|Hotrodford_88's Webpage]
Thread
Thread Starter
Forum
Replies
Last Post
