This was my original post, and after a visit to the dealer the problem seems to have been fixed (see below):

We just put our new '05 F350 supercrew through it's first towingand off-road experiences, and had problems with the truck "surging" at very low speeds. It's a manual tranny, diesel; about 2800 miles on it.
Here's what happened:
1) towing the 5'er through the campground with a 10 mph speed limit, low gear and/or first gear, flat paved road, the truck would not hold a constant speed - it kept surging and letting off, and made the truck bounce around, which got worse and worse because you can't keep your foot steady on the accelerator pedal. We had to come to a complete stop and try to start up again, about 6 times to make it through the campground.
2) climbing up a fairly steep, rocky, clayey, wet, one-lane fire road, same thing happened when trying to slowly crawl along in 4x4 high (no trailer). Tried putting it in 4x4 low, and it was no different. Ended up having to run through 4 gears in 4x4 low to about 20-25 mph to get the rpm's up enough to hold steady and seriously fly up the road without surging. (On the plus-side, I'm ready for desert racing now!)
Previous to this truck we had a V-10 manual F250, and never had this problem at all. This is our first diesel - can someone tell me what is going on and what to do to fix it?
Much appreciated!!
~~~~~TrekChick

The fix for the problem was to replace a faulty EBP (Exhaust Back Pressure) Valve. Apparently when the turbo was running at 25 psi the "map baro and EBP correlation" showed the EBP reading 13.3 psi, so they replaced the valve.

~~~~~TrekChick

 

Keep us posted on the long-term results. While I'm not surprised that the EBP sensor was bad, I'm not sure I understand how 25psi of boost pressure has something to do with "very low speed" surging. Or was that just the test pressure at which the EBP sensor discepancy was detected? [IMG][/IMG]

 

Yes, I believe that is the test pressure - I just copied what was on the statement they gave me.

Went trolling through the Lowe's shopping center today - lots of speed bumps & pedestrians (I guess everyone is out doing their Dad's-day shopping today) - so I had a great chance to monitor the fix while trying to keep it around 10 mph. It seems to be fixed. Holds a very steady speed now, even when bouncing over the speed bumps. On the road it seems to be running smoother up through all the gears, and I think it's quieter now??? Maybe just my imagination.

I just wonder if that valve always needs to be replaced every 3500 miles?????? Or if it was just a bad one out of the box?

~~~~~TrekChick

 

I still have the original on my 03. Many technicians have over looked the EBP sensors. Good to see you have a great service department to solve the mystery.

 

I just wonder if that valve always needs to be replaced every 3500 miles?????? Or if it was just a bad one out of the box?
Bad one out of the box...

 

Right!!! Well, it's happening again...... A couple weeks after the EBP-valve replacement we towed the trailer on a 1000-mile trip with no surging problems at all. (However we did blow the innercooler hose - see my other thread about THAT wonderful experience! https://www.ford-trucks.com/forums/s...d.php?t=388032 ) Had no problems with surging when off-roading the following weekend. Last weekend, towed the trailer about 200-miles, and the surging, buckin' & snorting has resurfaced again - and I think it's worse than the first time. It happens at all speeds now; mostly when towing, but even without the trailer. Noticed it happened more than once when we are accelerating up a grade, like a freeway on-ramp, that levels off, so you back off on the accelerator, and that's when it starts surging. With the 5'er hooked up it is BAD - very BAD - major slamming on the king pin. It won't stop if you let off the accelerator; it only stops if you let off and put in the clutch at the same time. It has happened with different people driving, so it's not a driver-thing. It also happens when trying to drive at a slow, constant speed; like 10 mph in a parking lot, for example.
Back to the dealer AGAIN next week. 3rd time in six weeks. GEEEEZE
~~~~~TrekChick

 

hmmm....
Doesn't sound good at all, sorry.
That valve shouldn't be fine, and last the life of the truck.
I hope you have a nice understanding dealer.
We are here to help you.

 

TrekChick, ask the dealer to specifically check the ICP sensor, the ICP connector, and the IPR valve. The symptoms you describe sound similar to other people's experiences, including my own, where one or more of these parts go bad and causes the PCM to have spasmodic fits as it tries to maintain the correct injection pressure as your demand for power varies. In my own case, the ICP connector was replaced and, voila, no more surging.

My second guess would be a turbo-related issue, such as a bad VGT control valve or stuck vanes. I normally would suspect the EGR valve next, but since the dealer didn't find any P040x codes your first time around, it doesn't seem as likely.

 

Here is some info I got about the safety recall.

Safety Recall 05S34, 2004 F-SuperDuty, Excursion and Econoline:

Affected vehicles are 2004 F-SuperDuty/Excursions built between 9-29-03 and 5-31-04, and Econolines built between 12-9-03 and 5-28-04. On all F-SuperDuties/Excusrsion the FICM harness will be inspected for chafing/damage. If damage is found, the harness will need to be replaced (estimated less than 2% of vehicles will require this action). If no damage is found a harness protection kit will be installed. On these trucks built between 12-1-03 to 5-31-04 the ICP sensor connector will be replaced due to the possibility of a poor crimp on the factory connector terminals. The Econolines covered under this recall only get a replacement ICP sensor connector.
Revised 7-6-05: The F-Seires and Excursions will have the FICM harness part number inspected. If the harness has a tag with "C97" on it, no FICM harness repair is necessary.

Recall data for: 2004 FORD EXCURSION
NHTSA Campaign Number: 05V270000
Manufacturer Campaign Number: 05S34
Make: FORD
Model: EXCURSION
Year: 2004
Component:
ELECTRICAL SYSTEM:WIRING
Manufacturers Involved: FORD MOTOR COMPANY
Begin Date Of Manufacturing: 20030929
End Date Of Manufacturing: 20040531
Recall Type: V
Potential Number Of Units Affected: 180104
Date Owner Notified By Manufacturer:
Recall Initiator: MFR
Manufacturer Responsible For Recall: FORD MOTOR COMPANY
Date Report Received By ODI: 20050610
Date Added To File: 20050610
Regulation Part Number:
Federal Motor Vehicle Safety Standard Number:
Defect Summary:
CERTAIN PICKUP TRUCKS, SPORT UTILITY VEHICLES AND VANS EQUIPPED WITH 6.0L DIESEL ENGINES MAY EXPERIENCE STALLING WITHOUT WARNING WHILE DRIVING AND MAY OR MAY NOT RESTART.
Consequence Summary:
SHOULD THE ENGINE STALL, A VEHICLE CRASH COULD OCCUR.
Corrective Action:
DEALERS WILL UPGRADE THE FUEL INJECTION CONTROL MODULE (FICM) WIRE HARNESS OR REPLACED, AND/OR HAVE A NEW INJECTION CONTROL PRESSURE (ICP)) SENSOR CONNECTOR INSTALLED. THE RECALL IS EXPECTED TO BEGIN ON JULY 5, 2005. OWNERS SHOULD CONTACT FORD AT 1-800-392-3673.

 

Moebdick - I will ask to have those specific things checked out. Sounds exactly like what's happening.

Interestingly enough, when I was in last week for the innercooler hose replacement, they ran my truck through Oasis, and said it is not subject the wiring recall; nor have I received a notice in the mail. My build date is somewhere between 01/01/05 when I ordered it, and 02/18/05 when I took delivery. I saw some photos on a diesel mechanic's website of the damage caused by the wires rubbing on a bolt-head, that leads to the shorting-out. I was wondering, since I have the "rare" manual tranny, am I missing the offending bolt? I thought for sure I'd be on the list (thankful I'm not - I have enough problems already!!)

I really appreciate everyone's input - I have learned a LOT from this website. Thanks, Boys!!

~~~~~TrekChick

 

Here is another recal/TSM:

2004 Emissions and EBP Sensor Recall 05E15:

Certain 2004 trucks are being recalled for computer reprogramming and replacment of the Exhaust BackPressure sensor and, in some cases, the EBP sensor connector. Econolines built between 12-9-03 through 5-28-04, and SuperDuties and Excursions built between 12-1-03 through 5-31-05 will have the EBP sensor connector replaced. SuperDuties and Excursions built between 9-29-03 through 11-30-03 do not have the connector replaced. All of the above trucks will be reprogrammed to the latest calibration level. Since many trucks ahave already had the EBP sensor replaced with the current level part, the sensor part number should be inspected. If the part number on the sensor is 1850353 over a number starting with "C1", the sensor does not need to be replaced. Any other numbers, or unreadable numbers, will be replaced

 

Recall 05E15 has been suspended as of 7-18-05. I took my truck, 04' 6.0L Super Duty, build date March 04, to get serviced on the 7-12-05 at the local ford dealership's quick service joint. They told me that there was two recalls out on my truck, 05E15, EGP sensor and 05S34, FICM work. I made an appointment (7-20-05) at the dealer to have the recalls done. Then I checked the diesel doctors web site and found out that there is a third recall out on my truck, 05B29, R&R cold side intercooler pipe. Well the days went by and I took the truck in and they told me the recall, 05E15 was suspended, so I'm stuck with what might be a faulty EGP. The other recalls were completed.

 

Here's an update to the surging saga:
Took it in to the Dealer on Thursday morning; Thursday evening they called and said they ran all the diagnostics, and the truck gave no codes. They drove it and could not duplicate the surging. I went in Friday afternoon and had the service manager ride with me, and I was able to duplicate the surging at low speeds (thank goodness - at least he knows I'm not imagining it!). The surging is much worse when the truck is under load = towing the 5'er. He told me that just that very day a guy with the same truck - 2005 F350 4x4 CC 6.0L w/ manual tranny - came in with the SAME story. (I think the manual tranny is key here, for some reason.) He's the only other owner that has come in with this problem, besides me. He has a welding rig on his truck, so he's got the heavy load, too. Unfortunately this guy's truck also threw no codes. Ford says they have an engineer coming by next week to look at the welder's truck, and when they find out what day he'll be there, they'll call me back, too.

One of the things I don't understand is that the first time I brought it in, they replaced the EBP valve, and the surging stopped. But this time, same symptoms, no replacement. And the surging did not start up again until after Ford worked on replacing the blown innercooler hose. For whatever that's worth????? Coinicdence?? Or not??

Keep yer fingers 'n' toes crossed for me!!
~~~~~TrekChick

 

I think I would accidentally on purpose have my truck at the dealer next week as well. Why have the big shot Ford engineer look at one when he can look at two?