So the lesson here is don't plan a long trip on a holiday weekend.

My '01 7.3 has decided it didn't like to pull up a hill. We are pulling a fifth wheel RV and when we get a long hill it will start to miss like it only has 4 cylinders. If I let it slobber along at about 20mph on the shoulder for a while it will clear up and run again until the next hill. Runs great on the flat, 70mph no problem.
We are sitting in Alberqueque, NM on our way to western Colorado with plenty of hills in between. No body to work on it until Tuesday.
Any ideas? Fuel pump, injector pump, fuel filter, cat?

 

LOL... I was wondering what I was going to find in this thread from the title...

It would be a lot of things. I'll take a guess that you don't have gauges, right? Was there a CEL? If so, find someone that can read PowerStrokes (no, the plain-Jane Auto-Zone readers won't do it). If you can get us codes, we can go from there.

Oh, and welcome to FTE!! We're a pretty helpful bunch. I know we have a member or two in Albuquerque -- maybe one of them will chime in...

 

Sorry to hear about your situation. Is it chipped? Check engine light?
Have you tried any of the following?

- CPS
- HPOP reservoir level
- Fuel Filter
- Under Valve Cover Harness
- Can you here the pump when you turn the key?

Edit - Dang it Izzy, your always on it....

 

And that's AFTER a dose of Flexaril & Vicodin!! Keep up, man!!!

 

Sounds like fuel supply to me. Have you ever cleaned the in tank screens?

 

Thanks for the quick reply.
I always get the "service engine soon" light when I get on it hard. Stays on awhile and then will go out if I'm not towing.
It is chiped but I don't have any info on it. We bought the truck this spring with 130k on it and the chip was in it. The seller said it was only 45hp. Just has a **** on the dash...nothing more.
Fuel filter was changed about 3k ago but that probably doesn't mean much.
I do hear the fuel pump for a few seconds when I turn the key.

 

Fuel tank screen kind of makes sense.
Izzy mentioned the HPOP reservoir. What's that?

 

I would start with trying to remove said chip to see if it still acts up.

 

I'd agree with pulling the chip. You're probably getting P1211 codes when you get on it hard and the most common cause for that is poor programming.

 

I would have to disagree with it being because of poor programming. You get a P1211 because the HPOP can't provide the pressure that the programming is calling for. That can be due to a pump that is getting tired or because it is a high horsepower tune that is just asking to much. This can happen with any of the tuners that I am aware of.

 

did you notice anything with your engine temps?... sometimes if the truck gets real hot pulling a hill... like 260 range it will go into a limp mode. The truck will fall flat on its face by limiting ICP. I don't think it is your issue... but if you have a stuck thermostat or you are low on coolant then it could be hot... you wouldn't even notice this unloaded cruising... but with a trailer you would.

I hate to ask this... did you check the oil level?

 

Right, a bad, high horsepower program is asking the HPOP for things it can't produce, therefore bad programming. I just know from my own experience that I had a chip with 40 and 50 HP tunes on it that would routinely throw P1211 codes. I put in a different chip with 80, 100 and 120 HP tunes on it that would not throw the same code with me driving it just as hard as I was the other chip. Datalogging on my HPOP showed it to be healthy (it was holding at 2500 PSI without any problems), so I'd say the programming was making unreasonable requests for 40 and 50 HP tunes. I'm not saying that any one tuner has this problem more than others, just that it's very likely that it's the tuner if he's getting the code just getting on it in an unloaded truck.

 

Thanks for all the replies.
The oil level is full, pressure is normal.
Temperature never goes above normal. Coolant level is full.
I'll just have to see what the local Ford dealer says on Tuesday.

 

So where did you end up getting stuck at?

 

How much does the engine shake when this happens? If it truly feels like it's just firing on 4 cylinders, then I'd suspect a loose plug on the UVCH, which you might be able to check with an ohm meter.

If your problems only happen while towing up hill, and it feels like the engine just loses power and maybe running out of fuel, then Clux has the best guess. The screens inside the mixing chamber (inside the fuel tank) are plugged up and the restriction under load is causing the problems.


How full is your tank and can you drop it where you're at?