| Pages:
1
2
3 |
SFandH
Elite Nomad
Posts: 7084
Registered: 8-5-2011
Member Is Offline
|
|
Engine Problem
I know there are many nomads who are good mechanics so I thought I'd solicit some opinions.
My 5.4 liter F-250, 150,000 miles, stumbles under light acceleration. It's a reproducible problem. If I accelerate normally to 2000 rpms all is good.
But if I take my foot off the gas, let the rpms fall to say 1200 rpms and then lightly accelerate so the transmission doesn't
downshift the motor noticeably stumbles at about 1500 rpms. I'm thinking about adding a fuel injector cleaner to the gas as my first option.
Watcha think?
[Edited on 7-10-2016 by SFandH]
|
|
|
Hook
Elite Nomad
Posts: 9009
Registered: 3-13-2004
Location: Sonora
Member Is Offline
Mood: Inquisitive
|
|
The injector cleaner cant hurt. I really like the Lucas Oil one. I live in Mexico and my Jeep seems to need a treatment every three months or so,
though it never needed it in the US.
Also try replacing any and all fuel filters and make sure your air filter is clean. Those are the easy things to try.
Is the "check engine" light on? If so, go by an Autozone and have them read out the codes.
[Edited on 7-10-2016 by Hook]
|
|
|
TMW
Select Nomad
Posts: 10659
Registered: 9-1-2003
Location: Bakersfield, CA
Member Is Offline
|
|
I think that is a good place to start. Did it just start doing this recently?
|
|
|
SFandH
Elite Nomad
Posts: 7084
Registered: 8-5-2011
Member Is Offline
|
|
I noticed it about a month ago, the problem went away, and then returned yesterday.
No check engine light. I have a code reader.
[Edited on 7-10-2016 by SFandH]
|
|
|
TMW
Select Nomad
Posts: 10659
Registered: 9-1-2003
Location: Bakersfield, CA
Member Is Offline
|
|
Can you relate it to a gas station.
|
|
|
SFandH
Elite Nomad
Posts: 7084
Registered: 8-5-2011
Member Is Offline
|
|
I use the same gas station for my car. No problems with it.
|
|
|
Hook
Elite Nomad
Posts: 9009
Registered: 3-13-2004
Location: Sonora
Member Is Offline
Mood: Inquisitive
|
|
Is it happening in really hot conditions? Yesterday was really hot in the entire SW and all of Baja. Was it really hot when it started a month ago?
Where are you?
|
|
|
SFandH
Elite Nomad
Posts: 7084
Registered: 8-5-2011
Member Is Offline
|
|
Yesterday I was on the toll road north of Rosarito. Not hot.
I'm really paranoid about transmission problems since over the years I've had two fail in baja, causing major headaches. Further Inet reading
indicates it's a fuel or ignition problem. So far I haven't read anything pointing to the transmission.
I'll look into throttle position sensors, thanks for the suggestion.
[Edited on 7-10-2016 by SFandH]
|
|
|
Bob and Susan
Elite Nomad
Posts: 8813
Registered: 8-20-2003
Location: Mulege BCS on the BAY
Member Is Offline
Mood: Full Time Residents
|
|
I think that's what it's called...the vaccuum hose fell off...
its way back by the fire wall behind all the intake "stuff"
probably no part needed...just reattach the hose...you may not be able to see its off from the front...you need to climb on top of the engine and
reach in
either that or its the fuel pump wire inside the tank...i'd get a new pump even though you can fix this
you need to take the tank out...if its out just replace the pump
i'll bet a loose hose...
tell us later what it was...
|
|
|
Bob and Susan
Elite Nomad
Posts: 8813
Registered: 8-20-2003
Location: Mulege BCS on the BAY
Member Is Offline
Mood: Full Time Residents
|
|
this is the guy to go to for transmission rebuilding...they have a "wear-house" of transmissions there...
here is a video
they are in sunland ca just north of Burbank
https://www.youtube.com/watch?v=BFIJB5n3BYQ
|
|
|
Hook
Elite Nomad
Posts: 9009
Registered: 3-13-2004
Location: Sonora
Member Is Offline
Mood: Inquisitive
|
|
I think if that hose was off, it would be happening a lot more than the situation he is describing. But it's an easy check. Look for ANY vacuum hoses
that are off.
I also think if it was the throttle position sensor failing, a code would be thrown.
Very unlikely that it is transmission related. Fuel related would be my first guess, then electronically-controlled fuel components, then ignition.
Ignitions don't go south too much anymore (except for German cars, LOL!). So, check the easy mechanical fuel items like filters first.
If the "lift" type pump in the fuel tank is failing for whatever reason, you typically wont be able to drive up a hill without the engine stumbling.
And that is such a PITA repair that only consider doing that when all else has failed.
|
|
|
Bob and Susan
Elite Nomad
Posts: 8813
Registered: 8-20-2003
Location: Mulege BCS on the BAY
Member Is Offline
Mood: Full Time Residents
|
|
Quote: Originally posted by Hook  | I
...I also think if it was the throttle position sensor failing, a code would be thrown...
...If the "lift" type pump in the fuel tank is failing for whatever reason, you typically wont be able to drive up a hill without the engine
stumbling. And that is such a PITA repair that only consider doing that when all else has failed. |
no code if the throttle sensor has a leak...ford didn't use a hose clamp...you should add one but its harder than hell to tighten
if the fuel pump is failing...it may be the ground wire and it goes on and off...if you hit a bump the engine may stall...it'll idle bad
|
|
|
willardguy
Elite Nomad
Posts: 6451
Registered: 9-19-2009
Member Is Offline
|
|
 .......clean the MAF/throttle body?
|
|
|
Hook
Elite Nomad
Posts: 9009
Registered: 3-13-2004
Location: Sonora
Member Is Offline
Mood: Inquisitive
|
|
.......clean the MAF/throttle body?
Are you talking about Mass Liquid Flow, while you throttle a body?
If so, yes, I prefer both components to be clean as possible. 
A Willarguy post deserves a Willardguy reply............
|
|
|
willardguy
Elite Nomad
Posts: 6451
Registered: 9-19-2009
Member Is Offline
|
|
| Quote: Originally posted by Hook | .......clean the MAF/throttle body?
Are you talking about Mass Liquid Flow, while you throttle a body?
If so, yes, I prefer both components to be clean as possible.
A Willarguy post deserves a Willardguy reply............ |
....mass liquid flow WILL lead to stumbling!
|
|
|
woody with a view
PITA Nomad
Posts: 15939
Registered: 11-8-2004
Location: Looking at the Coronado Islands
Member Is Offline
Mood: Everchangin'
|
|
Your answer lies within......
https://www.google.com/search?q=5.4+liter+F-250%2C+150%2C000...
|
|
|
fishbuck
Banned
Posts: 5318
Registered: 8-31-2006
Member Is Offline
|
|
I have the same motor, same issue.
It does't like to run at low rpm where is doesn't have much torque.
I'm guessing spark plugs. The fire goes out.
It's a horsepower motor like all gasoline powerplants.
It loves high rpm.
The spark plugs are a pain to remove and are prone to breaking during removal.
A special tool is required or I would have done it by now.
Manually downshift it. And let it roar. That's what it likes.
"A ship in harbor is safe, but that is not what ships are built for." J. A. Shedd.
A clever person solves a problem. A wise person avoids it. – Albert Einstein
"Life's a Beach... and then you Fly!" Fishbuck
|
|
|
SFandH
Elite Nomad
Posts: 7084
Registered: 8-5-2011
Member Is Offline
|
|
Lots of info on the Internet. All sorts of misfiring issues with this motor. Too bad, but it has been running perfectly for years.
I'm going to run some gas cleaner through the fuel system for a while and see what happens. It's an easy/cheap first step. I've read several mentions
of the Lucas cleaner being good stuff.
I couldn't find any detached vacuum hoses.
The fact that it stumbles only around 1500 rpm in high gear under light acceleration must point to a specific problem, what I don't know. And when it
stumbles it STUMBLES, it's like I'm hitting bumps in the road, very noticeable.
|
|
|
Hook
Elite Nomad
Posts: 9009
Registered: 3-13-2004
Location: Sonora
Member Is Offline
Mood: Inquisitive
|
|
Is this one of those engines that only fires a limited number of cylinders at certain RPMs?
|
|
|
Bob and Susan
Elite Nomad
Posts: 8813
Registered: 8-20-2003
Location: Mulege BCS on the BAY
Member Is Offline
Mood: Full Time Residents
|
|
| Quote: Originally posted by SFandH | ...I'm going to run some gas cleaner through the fuel system for a while and see what happens. It's an easy/cheap first step. I've read several
mentions of the Lucas cleaner being good stuff.
I couldn't find any detached vacuum hoses. |
there is NO cure for the common cold...don't waste your money on gas cleaners
the pipe larry was talking about is behind the throttle body...you can barely see it fron the front...you have to reach in...
I replaced mine...$30...a guy in California told me and the mechanic in mulege knew right away...he just reached in and plugged it back in...
again its way in the back
when my fuel pump went out...it would stall on speed bumps...and idle bad too...up and down
go see a mechanic...they will know...its not gas or plugs
|
|
|
| Pages:
1
2
3 |
![[*]](images/xmbforum/default_icon.gif){kind=icon}
