Bucking when hot
Thread Starter
|
Laughing Gas
Joined: Mar 2009
Posts: 1,028
Likes: 0
From: long island
Bucking when hot
When my truck is cold it runs perfectly. As soon as it gets to operating tempurature it develops a pretty bad miss. It idles rough and bucks terribly at low rpms. I dont think my egr is hung up because it still does it when i remove the vac hose. the egr valve is about 2 years old. Cap, rotor, plugs, and wires are also in the 2 year range. No codes. What else could make it run cruddy when its warm?
Posting Guru
Joined: Feb 2002
Posts: 1,712
Likes: 1
From: Atlanta, Georgia, USA
Relevant to the 4.9L I-6:
It would probably be worth your time to change out the TB gasket. Mine was sucked all the way into the contours of the idle air passages. Here's a video that walked me through it. It's a very inexpensive fix, but you'll make a mess cleaning out your old throttle body:
It would probably be worth your time to change out the TB gasket. Mine was sucked all the way into the contours of the idle air passages. Here's a video that walked me through it. It's a very inexpensive fix, but you'll make a mess cleaning out your old throttle body:
Thread Starter
|
Laughing Gas
Joined: Mar 2009
Posts: 1,028
Likes: 0
From: long island
I cleaned the throttle body and replaced the gasket with no change in behavior. icm and stator? is the stator inside the dizzy? wheres the icm? coil was replaced with my last tune up but I could swap another one in being that they are so cheap.
Fleet Owner
Joined: Oct 2005
Posts: 20,786
Likes: 1,751
From: Kentucky
For reference: Stator
The Ignition Control Module (ICM) is located on the distributor ('91 and earlier) or mounted on a heat sink near the driver side hood hinge ('92 and later).
Thread Starter
|
Laughing Gas
Joined: Mar 2009
Posts: 1,028
Likes: 0
From: long island
Yes, the stator (PIP) is inside the distributor
For reference: Stator
The Ignition Control Module (ICM) is located on the distributor ('91 and earlier) or mounted on a heat sink near the driver side hood hinge ('92 and later).
For reference: Stator
The Ignition Control Module (ICM) is located on the distributor ('91 and earlier) or mounted on a heat sink near the driver side hood hinge ('92 and later).
ohh I actually did the icm once on this truck. its on the fender on my 92 like you said. looks like im gonna be fooling with the dizzy if the fuel filter doesn't help. ill look in the book how to test the icm.
Trending Topics
Posting Guru
Joined: Feb 2002
Posts: 1,712
Likes: 1
From: Atlanta, Georgia, USA
I don't know of any reasons why ignition system performance would fade when the engine gets hot. You can always check for spark with a spark tester, which is basically a dummy spark plug that you ground with a clip and a see-through window that makes it easy to watch for spark. If your truck starts and runs at all then the test is redundant. Do you have any CEL codes? That Hall Effect sensor inside the distributor is a real pain to change, and won't always be fixed by buying a new distributor from the parts house. In my experience, they cause a no-start or sudden failure condition rather than fade with heat. If the gas filter doesn't make it right, it's worth your time to do a solid diagnostic with a good multimeter (Fluke) and an oscilloscope. Hopefully it doesn't come to that- just did mine about 6 months ago!
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
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
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
Senior User
Joined: Mar 2014
Posts: 433
Likes: 0
From: southern maryland
don't mean to but in but as mentioned you need to pull the codes again and do you have a catalytic converter on your truck what do you have as far as tools like a volt meter vacuum gauge or a back pressure gauge things of the nature.
Thread
Thread Starter
Forum
Replies
Last Post
bigteal
1987 - 1996 F150 & Larger F-Series Trucks
11
Apr 26, 2011 09:11 AM
DJdemon6696
1987 - 1996 F150 & Larger F-Series Trucks
40
Aug 1, 2007 04:04 PM