5.4 falls flat on it's face
Thread Starter
|
Freshman User
Joined: Dec 2011
Posts: 36
Likes: 0
From: ne. pa.
5.4 falls flat on it's face
when this first started the truck would move out the drive way(fuel pump) the only thin that did was make my gauge work again. i then found 2 bad plugs and cop's. no better. i then changed the maf and o2s, both junkyard parts. a little better, the truck will now tach out at 2g rpm's. i then changed the temp and cam sensor. it will now tach out, but after a 10 mile ride it falls flat on it's face. i let it sit for 10 to 20 min and it will run for another 10 miles then fall.i also found that the intake bolts were loose. i can't find any vac leaks ,but it sounds like one near the tb. i can also hear a valve noise in cylinder 7 or 8. i am changing the intake gaskets,and pulling the valve cover to inspect the valves, and new plugs. any other ideas what else to look at? i had code 1130 cleared code after changing maf ,still no code. and when this all started i noticed the tach bounce a few hundred rpm's when i lift off the gas (fuel pump) i think fixed that. this is driving me nuts
Cargo Master
Joined: Feb 2011
Posts: 3,450
Likes: 13
From: Forest lake minnesota
I'm having the same problem. when mine first started the truck would move out the drive way(fuel pump) the only thin that did was make my gauge work again. i then found 2 bad plugs and cop's. no better. i then changed the maf and o2s, both junkyard parts. a little better, the truck will now tach out at 2g rpm's. i then changed the temp and cam sensor. it will now tach out, but after a 10 mile ride it falls flat on it's face. i let it sit for 10 to 20 min and it will run for another 10 miles then fall.i also found that the intake bolts were loose. i can't find any vac leaks ,but it sounds like one near the tb. i can also hear a valve noise in cylinder 7 or 8. i am changing the intake gaskets,and pulling the valve cover to inspect the valves, and new plugs. any other ideas what else to look at? i had code 1130 cleared code after changing maf ,still no code. and when this all started i noticed the tach bounce a few hundred rpm's when i lift off the gas (fuel pump) i think fixed that. this is driving me nuts
Thread Starter
|
Freshman User
Joined: Dec 2011
Posts: 36
Likes: 0
From: ne. pa.
'99 5.4 at sc, lb, srw, with a clean cat and 4:10 gears. trans,oil ps coolers. with esof elimination
i was getting a lean code on bank 2. that is one way i found the bad plug and cop. i replaced those 2 cops and plugs...no more miss.
i was getting a lean code on bank 2. that is one way i found the bad plug and cop. i replaced those 2 cops and plugs...no more miss.
Thread Starter
|
Freshman User
Joined: Dec 2011
Posts: 36
Likes: 0
From: ne. pa.
cat is cleaned out, first thing i thought of..then i remembered when i replaced the engine i cleaned the cat out. this truck ran great for about a year. then it started all at once.
New User
Joined: Jan 2013
Posts: 12
Likes: 0
if you had a faulty plug or cop then there's a chance you could melt your cats. its never happened to me in my truck just a car that I had. Same symptoms.
Trending Topics
New User
Joined: Jan 2013
Posts: 12
Likes: 0
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
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
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
Thread Starter
|
Freshman User
Joined: Dec 2011
Posts: 36
Likes: 0
From: ne. pa.
the damn thing will
idle all day just fine, but won't tech out past 3500 RPMs when warm unless you shut it down then it will tech out full red line
idle all day just fine, but won't tech out past 3500 RPMs when warm unless you shut it down then it will tech out full red line
Thread Starter
|
Freshman User
Joined: Dec 2011
Posts: 36
Likes: 0
From: ne. pa.
i can "almost" rule out a hg. no oil in the water or water in oil and not using water. other than normal, but one never knows...
Thread Starter
|
Freshman User
Joined: Dec 2011
Posts: 36
Likes: 0
From: ne. pa.
if it was compression , why will it idle all day with no problem. it only acts up after driving about 10 miles, or after it warms up.it will run like a raped ape when cold...and fuel pressure is at 30 psi @idle and up to 45 psi @ 3g rpms..
FTE Leadership Emeritus
Joined: Sep 2000
Posts: 23,174
Likes: 1,678
From: Stephensville WI
One engine I had also had a problem...would get to a certain RPM then refuse to go any faster. That issue was the timing chain was about to expire, it had stretched so much it allowed the camshaft (just one on that engine) to slip a few teeth.