extremely frustrated
Thread Starter
|
New User
Joined: Aug 2005
Posts: 16
Likes: 0
extremely frustrated
Let me start by saying I have been searching the forum for weeks about this problem.
2000 f350 cc4x4 automatic 170,000 miles
Heres the problem. The truck is getting a lean code on both banks. When I am driving and try to accelerate the truck tries to downshift, but the motor starts sputtering. It is not a miss. It is like it is out of gas. I have changed the MAF,IAC,TPS and pulled the fuel pump out to check the filter. The fuel pump intake filter was dirty I cleaned it and reinstalled it. The fuel filter is new, so is the air filter. The dealer has no clue what the problem is. When the trusk downshifts it just continues to sputter and eventually it will die. Here is the kicker I can put the truck in nuetral turn it off then back on and it will be fine for 10 or 20 more miles. I dont think it is a tranny problem because the other day it was idling and it starting sputtering and then died. The truck uses 1 qt or less between changes, it has n o leaks anywhere. I have checked all the vacum lines and have found no leaks. I sold a PSD that was having power problems and now I am having problems with new truck. I can't win. Please help if you can, thanks
2000 f350 cc4x4 automatic 170,000 miles
Heres the problem. The truck is getting a lean code on both banks. When I am driving and try to accelerate the truck tries to downshift, but the motor starts sputtering. It is not a miss. It is like it is out of gas. I have changed the MAF,IAC,TPS and pulled the fuel pump out to check the filter. The fuel pump intake filter was dirty I cleaned it and reinstalled it. The fuel filter is new, so is the air filter. The dealer has no clue what the problem is. When the trusk downshifts it just continues to sputter and eventually it will die. Here is the kicker I can put the truck in nuetral turn it off then back on and it will be fine for 10 or 20 more miles. I dont think it is a tranny problem because the other day it was idling and it starting sputtering and then died. The truck uses 1 qt or less between changes, it has n o leaks anywhere. I have checked all the vacum lines and have found no leaks. I sold a PSD that was having power problems and now I am having problems with new truck. I can't win. Please help if you can, thanks
Post Fiend
Joined: Jan 2002
Posts: 5,859
Likes: 7
From: USA
Fuel pressure regulater or fuel pump! pump is in the tank
Have you done a fuel pressure test off the fuel rail?when it dying ?can you hear the pump running when its dying also ,would be a good thing to chk.
Rich
Have you done a fuel pressure test off the fuel rail?when it dying ?can you hear the pump running when its dying also ,would be a good thing to chk.
Rich
Senior User
Joined: Oct 2005
Posts: 127
Likes: 0
From: Crystal Lake, IL
I agree. Check your fuel pressure. You may also have a kink in your return line. If your fuel pressure is fine, try blowing out your fuel lines. If air is just squeeking by but nothing solid coming out, look for kinks. This happened to me before.
Thread Starter
|
New User
Joined: Aug 2005
Posts: 16
Likes: 0
pressure test
I did a pressure test today.
40 psi with key on engine off
35 psi at idle
These readings are right in line with the service manual.
I have checked all the fuel lines and they look fine..
I still have no idea.
The only difference is that it seems to be sputtering all the time now. I could only get up to 45mph today. If I gave it any gas it would almost kill the engine.
40 psi with key on engine off
35 psi at idle
These readings are right in line with the service manual.
I have checked all the fuel lines and they look fine..
I still have no idea.
The only difference is that it seems to be sputtering all the time now. I could only get up to 45mph today. If I gave it any gas it would almost kill the engine.
Elder User
Joined: Aug 2005
Posts: 747
Likes: 0
From: Mesa, Arizona
Trending Topics
Post Fiend
Joined: Jan 2002
Posts: 5,859
Likes: 7
From: USA
What did the pressure do at part throttle?
Okay what was the exact code you had ?
Also were there pending codes before the last one?
What I'm saying is the last code displayed is not always the problem.It may just be the resulting code from a prior problem. A lean code on both banks can be from a faulty 02 sensor downstream causing the pcm to adjust fuel trims lean. thus your next code would be the upstream o2's to read lean
Take a look at the o2's while running with a good scanner to determine if the are all switching properly.
This just a suggestion,may not not be the cause.
It could be a leak at the pcv elbow or intake o-rings gaskets.
Rich
Okay what was the exact code you had ?
Also were there pending codes before the last one?
What I'm saying is the last code displayed is not always the problem.It may just be the resulting code from a prior problem. A lean code on both banks can be from a faulty 02 sensor downstream causing the pcm to adjust fuel trims lean. thus your next code would be the upstream o2's to read lean
Take a look at the o2's while running with a good scanner to determine if the are all switching properly.
This just a suggestion,may not not be the cause.
It could be a leak at the pcv elbow or intake o-rings gaskets.
Rich
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
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
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Thread Starter
|
New User
Joined: Aug 2005
Posts: 16
Likes: 0
just a thought
Is it possible that a clogged catalytic convertor could cause this problem?
I was having a loss of power with my PSD and the cat was plugged up solid.
If so would it give any codes?
I have no modifications on the truck.
The only codes have been p0171, p074
There have been no other codes
I was having a loss of power with my PSD and the cat was plugged up solid.
If so would it give any codes?
I have no modifications on the truck.
The only codes have been p0171, p074
There have been no other codes
Senior User
Joined: Oct 2005
Posts: 127
Likes: 0
From: Crystal Lake, IL
I personally believe that a clogged cat would not cause a lean code to appear. I think FortyFords has a great suggestion. A bad egr would also cause a rise in exhaust temps which could be mistaken for a lean mixture, maybe. Wudya think Forty?
Post Fiend
Joined: Jan 2002
Posts: 5,859
Likes: 7
From: USA
Rob, usually with a bad egr you will get p0400 or p0401 code with a reference to dpfe sensor.
I'm still thinking fuel delivery here!
even though the presures were right at idle and keyon engine off ,he may have a pump that can't provide the volume at part throttle.
lets see
filter has been changed
iac
maf
tps
fuel regulator ???????????
see these codes he got were adaptive fuel strategy codes,in other words caused by
something telling the pcm to go lean.but also could be a true lean condition
thats what i hate about obdii.
Unless you tie it all together with freeze frame data from the scanner its tough shooting from the hip here
Rich
Rich
I'm still thinking fuel delivery here!
even though the presures were right at idle and keyon engine off ,he may have a pump that can't provide the volume at part throttle.
lets see
filter has been changed
iac
maf
tps
fuel regulator ???????????
see these codes he got were adaptive fuel strategy codes,in other words caused by
something telling the pcm to go lean.but also could be a true lean condition
thats what i hate about obdii.
Unless you tie it all together with freeze frame data from the scanner its tough shooting from the hip here
Rich
Rich
Last edited by FortyFords; Oct 30, 2005 at 09:54 PM.
Senior User
Joined: Jan 2005
Posts: 122
Likes: 0
you need to check your mass-airflow sensor. Ford uses the maf sensor to help aid in the transmision shifting. If the mass air sensor is dirty or clogged with trash and dirt you will get this problem. And then again it does kind of sounds like a fuel problem. Try checking your fuel flow. sometimes you can have the preasure but not the flow.
Last edited by machanic; Oct 30, 2005 at 10:58 PM.
Guest
Joined: Nov 2004
Posts: 7,988
Likes: 55
From: north west new jersey
lean is mostly caused by a pluged air filter, unmetered air, low fuel pressure or a bad maf senser, since you changed it have good fuel pressure. and checked the rest. go back and carefully check all the vac. hoses for small crackes or being soft and check the intake manifold gaskets by spraying brake clean or carb cleaner at the gasket areas and around the hoses and see if it smooths out.
Elder User
Joined: Jun 2005
Posts: 645
Likes: 2
I was getting a P0171 & P0174 on our Windstar after 110k miles. I kept resetting it and it would come back within 20 miles of driving. Googled it and came up with all sorts of horrifying results like intake gaskets, butterfly gaslets, etc. It turned out to be a PCV problem. Oil had rotted the rubber hose out creating enough of a leak that it was lean. New hose from the dealer ($35!?!?) and problem solved.