About a month ago my friend purchased this vehicle and she absolutely loves it. Unfortunately yesterday afternoon she was driving down the road and experienced a loss of power and then the engine stalled. She pulled it to the side of the road and attempted to restart to no avail. We had no choice but to leave it for the night. We made arrangements to have it towed this morning so that should be taken care of.

Here are the symptoms. She accidently ran the front tank empty (fuel gauge does not read for this tank) and I've heard that's a bad thing (both in the diesel supplement and friends that have driven this model). After switching to the rear tank and cranking for a while it eventually fired up and appeared to run with no issues.

Approximately a week ago the fuel filter light illuminated and so I discussed with her that we should replace the fuel filter. As she lives 90 minutes away we had planned to perform the replacement yesterday afternoon. I read the manual and watched a number of videos and it seemed fairly straightforward. On Saturday she mentioned a loss of power which I attributed to the possibly clogged fuel filter. I reasoned maybe some debris had been picked up from the bottom of the tank and thus gunked up the fuel filter. High winds yesterday caused me to put off the replacement.

Unfortunately on her way back the above mentioned symptoms and stilling occurred forcing me to make a trip to provide her assistance. I picked up a fuel filter (Duralast which is an AutoZone brand but the only one they had in stock, not may preference but I had to get what was available). In 45 MPH I successfully replaced the filter (very simple, nice design Ford) and we attempted to start the truck. Unfortunately the batteries had been discharged from the previous cranking so we hooked up the jumper cables, let it charge for a few, and then cranked it over.

It slowly started to exhibit signs of life and eventually we got it started. When she attempted to drive the vehicle stalled once again and no amount of coaxing would bring her back to life.

While on the side of the road a Power Stroke mechanic happened to drive by and stopped to lend a hand. His road side diagnostic is that it is likely not getting fuel. He mentioned a common problem with the dual tanks is the valve which switches between the tanks.

All done and said I believe she is going to have it towed to the shop he works at (which specializes in trucks like this) which, thankfully, was only 3 miles down the road. I intend to have him address this issue as well as inspect it for other issues.

My question is: Do you think this could have been the result of her running the front tank empty? She didn't appear to be having any running issues with it until that happened. As mentioned we intend to have a mechanic diagnose / repair the issue I decided I'd post here to get people's thoughts while we wait.

It's a great truck and she's still happy with it. We expected some things would require some work here and there but didn't know any mechanics who were familiar with these trucks (my preference is to have mechanics who specialize in a specific manufacture / make work on vehicles, generic is OK but specialists are more familiar with the common issues).

Thanks for reading all this if you 've made it to this far.

 

Sounds like you are on top of it with the Ford 7.3 mechanic.
There could have been a number of things triggered by running out of fuel. Everything from air in the system to water / tank sediment being picked up to the fuel pump failing. Then we also have the cam position sensor that is a go to on these rigs in a no start scenario.

I have a 96 PSD that has over 250,000 miles on it. I love the truck and my wife understood in no uncertain terms that when we picked up the 350 diesel Dually for heavier work that the 250 would stay in the stable and not be sold.

So, yes problem could be running it dry, although I’ve never experienced any problems with that other than occasional coughs and stutters for the first 30 to 50 miles after doing it.

 

The seller noted he had replaced the CPS right around the 100K mark so my thought is on some fuel delivery problem. Of course with 171K on it now the replacement CPS could have failed again.

Glad to hear that no permanent damage should occur if the fuel is completely depleted. One other thing she noted, the rear tank fuel level stopped working after running the front tank out of fuel. I wonder if this is a symptom of the problem in that the tank switching isn't functioning correctly? Though both tanks have fuel so it's not a lack of fuel in the tanks. Oh, another thing to note...they ended up draining the fuel filter bowl while waiting for my arrival. When I arrived the bowl appeared to have a full level of fuel. This to me suggested some amount of fuel was flowing from the tanks. It's my understanding there is a low and high pressure fuel pump so it seems to me the logical pump to have failed would be the high pressure pump (I believe the low pressure pump brings the fuel from the tank and through the fuel filter and then on to the high pressure pump).

Anyway they're working on getting it towed to the shop but it might be a few days before they can look at it.

 

I believe they had drained the bowl prior to my arrival (I had advised them to do so as a troubleshooting step). However I can't be certain.

At this time it's at the mechanic and they're going to perform a comprehensive inspection on it (at not cost) and let me know all that needs to be addressed. Of course the immediate no start is first on the list. We did discover a leak when the vehicle was not level so I asked them to ensure they checked into that. The earliest they said they could look into it is Monday so I won't have any updates until next week.

 

You truck does not have a high and low pressure fuel pump. It has one fuel pump and it's located under the y-pipe that connects the turbo to the intakes. When that pump goes out it sprays fuel out a weep hole and fills the engine valley with fuel. Your issues are most likely related to the switch, and running it out of fuel. The fuel filter allert is usually a call to drain the water out of it. There's a yellow lever on the side of the filter housing that allows you to do that. DO NOT DO IT WITH IT RUNNING!

Your truck, or your friends truck in this case, does have a high and low pressure oil pump. If either one of those were to go out, that would cause your truck to stall and not start. But that is a rare situation to have happen, either one really, of failing. Get the switch fixed, along with the fuel gauges, and I would always keep at least a 1/4 tank of fuel in the tanks.

 

Thank you for the clarification on the fuel / oil pumps. Perhaps I had them confused. The mechanic who stopped to see if we needed help mentioned the fuel tank valve as a possible culprit. He said they're known to fail and that's a possible cause. Of course this comment was based on our description of events that led up to the stalling / no start. Currently it's at the shop but they won't have time to look at it until Monday. I'll keep everyone apprised of the solution when it is known.

 

The problem ended up being something as simple as running out of fuel. I can't explain how this happened as I was not present when it occurred but it was a "repair" that $50 worth of fuel took care of.

With the immediate no start condition addressed I had the mechanic perform an inspection and overall it is in very good condition. Much of what needs serviced are things which one would expect with a vehicle this age / mileage. There are a few things which I am having serviced with the two primary (and most expensive) being

• Fuel pressure sensor (which is the cause of the fuel filter dashboard light being illuminated)
• Fuel level sender for the front tank (in an effort to avoid future issues such as this)

These two items represent over half of the repairs / service I am having performed. Other items are coolant and clutch fluid flush (third most expensive work, it's a thirsty beast), front shaft rear u joint, and parking brake adjustment. In a couple of weeks I'll also have the shocks replaced and an alignment. The front crank seal is also leaking but they didn't recommend an immediate replacement but rather keeping an eye on it. Though I may just have them replaced it as it looks to be a $350 job, not bad at all.

Overall very pleased with the condition, I doubt she could have purchased anything for the price which wouldn't need some attention.