96 f250 runs like crap

OuchThatHurt

Member
Joined
May 19, 2011
Messages
247
Reaction score
0
Location
Neah Bay Wa
Alright. Little history on the truck. Previous owner (2nd owner) had the truck for ~9 years and put 8k miles on it. Sat in his barn A LOT. Told me pretty much the only thing has done to the truck is swap glow plugs, change the oil and a new vacuum pump. Body is perfect... thought I stole it off this guy...

When i test drove it I noticed about 1800-2500rpm it bogged down pretty good like it was starving for fuel or air... then would clear up and pull hard at 2500+ rpm with full boost (by sound, no guage). After i run through this cycle the truck will also hunt while at idle and the the engine shakes pretty good... but if I drive super old man and just (basically) idle around town... it idles fine. Weird!

So the first thing I checked (after doing some googling) was the EBP sensor. Clogged up 100%. Even the fitting of the ex. Manifold was clogged. Got a new sensor and cleaned the line/fitting. (New line coming in mail, just gonna replace it) truck continued to run the same. Next I unplugged the ICP sensor to see what would happen at idle. The only thing I noticed is a slight rpm surge for the first second then would drop about 50rpm while unplugged. Plug it back in and would ramp up maybe 50rpm. (Tach doesn't show this... guessing by sound)

The bad part
Should have been first on the list... but I finally got around to checking the fuel filter. Holy crap! It was as black as an oil filter with 30k miles on it. It was slimy and gunky and I don't know how fuel was even getting through that sucker. Un believable! (Any ideas on if it was dirty or if it has bugs? Never seen a fuel gilter so bad in the last 9 years and im a Marine engine mech) Anyways drained the bowl and replaced filter. Still no change in driving characteristics. I'm gonna pull the filter again today and vacuum out the bottom of the bowl and the little return hole in the housing. (Maybe the return mesh filter is backed up?)

Next I Did the BB mod in case my pump was just struggling after the fuel filter was so bad for so long. No change so I took the BB back out.

Does anyone think the vlv in the exhaust side of the turbo is staying closed until I reach max boost and forces it open?

I'm also gonna drop the tanks as soon as possible and clean the screens in the pick up.

I know it's a long read but if any of you have any ideas of stuff I can check without throwing 150 dollar sensors at it... it would be a huge help.
 

Attachments

  • 20170630_190519.jpg
    20170630_190519.jpg
    2 MB · Views: 75
  • 20170630_185224.jpg
    20170630_185224.jpg
    1.9 MB · Views: 63

ithumpwheniwalk

New member
Joined
May 22, 2011
Messages
381
Reaction score
0
Location
BC Canada
the ebp valve is very noticeable. I had a failure on my truck and it drove fine until the valve closed and then the truck slowed down and made a particular sound. It opened, closed and fluttered constantly until i wired it open. Certainly didn't make it run rough though.
 

OuchThatHurt

Member
Joined
May 19, 2011
Messages
247
Reaction score
0
Location
Neah Bay Wa
Alright... I'll probably leave the ebpv alone then. Only time I hear it is at start up when I closes to let the truck warm up faster.
 

ghohouston

Active member
Joined
Dec 2, 2012
Messages
4,023
Reaction score
15
Location
Lewisville,Texas
First things coming to mind are water in fuel after sitting so much/long
Bad injector o rings (would explain the black fuel filter)
Try unplugging the icp sensor and see if it changes anything.

Id also check the fpr screen
 

superpsd

Active member
Joined
Jun 10, 2014
Messages
1,928
Reaction score
3
Location
Missouri
I use Android device with OBDLink LX adapter. Torque pro and Car Gauge Pro. Under 100$.
 

TitoBandito78

New member
Joined
Jul 3, 2017
Messages
139
Reaction score
0
Until you get decent injectors it seems. Swamps or PIS.

And I believe the cats already out of the bag David lol
 

Chris2590

New member
Joined
Nov 2, 2016
Messages
126
Reaction score
0
Location
Bristol Indiana
You'd be surprised how many codes you have stored even with no check engine light. I'd start there first. That should point you in the right direction. Everything you've done so far is cheap or good maintenance anyways so that's good.
Good luck


Sent from my iPhone using Tapatalk
 

OuchThatHurt

Member
Joined
May 19, 2011
Messages
247
Reaction score
0
Location
Neah Bay Wa
I'm gonna hook an obd2 reader up and see if anything pops up. Gonna do a couple more small things. Dropping the fuel tanks is paramount after seeing the fuel filter on top of the motor.
 

crcrawford87

New member
Joined
Jul 16, 2015
Messages
43
Reaction score
0
Check the screen in the filter housing behind the regulator


Sent from my iPhone using Tapatalk
 

OuchThatHurt

Member
Joined
May 19, 2011
Messages
247
Reaction score
0
Location
Neah Bay Wa
Alright. So I cleaned out the fuel bowl... Probably a 1/2" of crap in the bottom, and cleaned the return screen (wasn't terrible) I also removed the fuel bowl heater because it was broke in 2... Probably the original.

Next... I had a brain fart and had a buddy turn the key to the on position and nothing happened.:doh: so I asked said buddy the bump it over to engage the mechanical pump. (fuel bowl is completely empty, even the black plastic tube)... well he starts the truck. Since he couldnt hear or see me the truck maybe ran for 3 seconds before he shut down. Im no rocket scientist but shouldnt the mechanical pump at least of filled the bowl half way up? I didnt even fill it up enough to flow over the collar where the black tube screws into.

Anyways, I got it all back together and it still runs like it's got a fuel issue between 1400ish and 2300ish rpm....

Still need to get an obd2 reader and drop the fuel tank I guess...
 

Magnum PD

Active member
Joined
May 18, 2011
Messages
9,566
Reaction score
6
Location
VA
Those terminals are for the glow plugs.

Fuel pump should have some fuel pumping in the bowl. Might be a bad pump.
 

OuchThatHurt

Member
Joined
May 19, 2011
Messages
247
Reaction score
0
Location
Neah Bay Wa
I'm definitely at a loss then. I just don't understand how it idles fine... runs like it starting for fuel, or isn't making enough hpop to run mid range rpm, then just about max rpm runs perfect, clears up, then roles out. Also, when accelerating and it's stuttering and almost falling off, if I let off the pedal it idles fine... idles fine, 1500-2500 runs Luke crap, 2500+ runs fine
 

ithumpwheniwalk

New member
Joined
May 22, 2011
Messages
381
Reaction score
0
Location
BC Canada
I'm definitely at a loss then. I just don't understand how it idles fine... runs like it starting for fuel, or isn't making enough hpop to run mid range rpm, then just about max rpm runs perfect, clears up, then roles out. Also, when accelerating and it's stuttering and almost falling off, if I let off the pedal it idles fine... idles fine, 1500-2500 runs Luke crap, 2500+ runs fine

you still haven't said if you've checked for codes. or put any kind of diagnostic equipment on the truck. there's lots of stuff to replace without ever solving your problem.

it's easier and cheaper to spend a few bucks and get/rent something to datalog. just my .02 cents :rockon:
 

Latest posts

Members online

Top