'01 F-350 Stalls but restarts

mchan68 · September 18, 2009

One of my many "projects" on the go here. I have an '01 F-350 that the customer complains of stalling. Vehicle is able to restart right away. Vehicle was in last week. Monitored EBP, MAP, BARO, ICP volts & psi and IPR duty cycle. All were well within specs that I recall on any 7.3L except EBP. EBP was reading 53 psi at KOEO and KOER and set DTCs accordingly. Noticed fuel filter was BLACK (like it hadn't been changed in LONG time) and the fuel heater connector burned. After replacing the EBP (now reading 14.5 psi) and an entire fuel filter and housing COMPLETE (new fuel heater, drain valve and WIF sensor), as well as the outstanding 07S57 CMP, the truck returns with the same complaint. Road tested, sure enough the truck began to run a little rough like it was about to stall, but never actually did before I was able to limp it back to the shop. To me it felt like it was running out of fuel. I called up one of my diesel "go to" buddies at another dealer. He's of the opinion that the high pressure pump is cavitating. So, his suggestion is to monitor ICP pressure with the engine redlining at 3400 RPMs for five minutes to see if ICP increases to about 3000ish, and if so call a high pressure pump and an IPR valve. What do you guys think? Does this make sense? I just don't want to spend more of this guy's money without being sure. The engine oil IS clean and clear like it was changed yesterday, by the way so I doubt the oil is foaming.

Aaron · September 18, 2009

Fuel pressure?

I had one doing the same thing, and the filters were plugged in the sending unit.

Power seem ok, even when it's running like poop?

mchan68 · September 18, 2009

Power seem ok, even when it's running like poop?
After the first repair, this thing felt like the cleanest and fastest 7.3L I ever drove.

Originally Posted By: Aaron

Fuel pressure?

Don't know. Never checked.

Originally Posted By: Aaron

I had one doing the same thing, and the filters were plugged in the sending unit.
That's what I was thinking it may be, or at least felt like to me. But my "go to" buddy seems to insist that it's the high pressure pump and IPR valve. What did you quote for this repair? Are you referring to the fuel tank "sock"?

Damon · September 18, 2009

An ICP related issue like aeration or cavitation would cause a hard restart, extended crank and rough run both before the stall and after restart. I'm with Aaron here, I think the screens in the sending unit module are clogged. We see a LOT of these nowadays.

That's not the "sock" since it uses a suction strainer screen and there are 2 tubular screeds inside the sender module itself. Unknown to many, there's also an integral (and NOT replaceable) fine mesh screen on the rail mounted fuel pump inlet too.

mchan68 · September 18, 2009

Update: After waiting PATIENTLY for four days for the fucktards at work to get our laptop working again, it now flags a hard P0232. Checked for power and ground at the pump. Looks like a fuel pump it is. This would be the very first fuel pump I've ever had to replace on a 7.3L. Anyone else experience this?

LARRY BRUDZYNSKI · September 18, 2009

I think the screens in the sending unit module are clogged. We see a LOT of these nowadays.

I would also concur on the sending unit....

Also you may want to check the tank for rust or delamination. Been on a run of tanks here lately 7-8 in the last week.

Keith Browning · September 18, 2009

Shoot. We have had a run on tanks for the last three years!

cbriggs · September 19, 2009

Ive had a couple of pumps calf on 7.3s in the past couple years, as i recall they were all towed in, no run.

Bruce Amacker · September 19, 2009

I've been out of town this week and didn't keep up with stuff online, and did a redeye from Seattle last night so I'm working on zero sleep. To check the screens, either do the restriction test using adapter 014-00931-2 (a big T-hose), the restriction should be 6"hg max. I've seen them pull 29"+ when the screens were plugged. A backyard test is to pull the return fuel hose off and measure return flow. It should be strong, like a quart in 30 seconds. If not, the screens are likely plugged.

Good Luck!

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MattB · September 20, 2009

Update: After waiting PATIENTLY for four days for the fucktards at work to get our laptop working again, it now flags a hard P0232. Checked for power and ground at the pump. Looks like a fuel pump it is. This would be the very first fuel pump I've ever had to replace on a 7.3L. Anyone else experience this?

Make sure you check inlet restriction once you get a good pump on it. Like you said, those pumps hardly ever fail. Something made it go, likely a huge inlet restriction. I've had restriction as high as 28" and still run with 15 psi MGP for 15-20 min. Then it will lose power, start to stumble, and stall if you push it. Like the other guys are saying check the socks in the pickup for rust and dirt buildup if you have restriction. The last one I had was run like that for such a long time that it also collapsed the braided stainless suction line at the tank too.

Bruce Amacker · September 20, 2009

Other thoughts: We had a similar truck setting a FP code and blowing the fuse (I don't remember what code it was) with a harness rub just under the master cylinder. It might not hurt to take a look there for a short.

If the FP has died, it is likely from cavitation due to restriction from the screens in the tank being plugged. We've talked about the screens before, they're part of the pickup assy and are non-serviceable according to Ford. I do know of people who have taken them apart and cleaned them, but be careful of breaking the white plastic part of the cup during disassembly. If they're plugged, it probably needs a tank, too. I suggest a FP check on the road to verify FP.

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(This photo is from a previous post, disregard the right photo.)

Good Luck!

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mchan68 · September 21, 2009

This vehicle is a 2001 model year. I thought it was only on 1995 to 1997 model years that used a sock.

GregKneupper · September 21, 2009

Have done alot of pumps and pickup tubes here. At least a few a month.

Aaron · September 21, 2009

The truck I was talking about was a 2002, IIRC.

You have to take the little barrel thing apart on the fuel tank sender to get the screens out. This one would pull 25" vacuum on the pump inlet as soon as you fired it up, and would actually run pretty good. When you got on it, the fuel pressure would drop to 0 psi, and it wouldn't run half bad for about 1/2 of my "big circle" road test (roughly 10km, most of which is 90km/h and above)

(ahem. 6.21504 miles at 55.93536MPH Posted Image )

After the halfway point, the truck would start to lose speed. By the time I got almost back to the shop, it wouldn't go faster than about 35mph with the accelerator pedal pressed down to about the oil filter.

Seems to me, that it wasn't setting any codes, but I can't recall.

MattB · September 21, 2009

The one I was referring to was a 2000-2001. The socks are inside the pickup assembly. I had codes set along the lines of "ICP uncontrollable", but I couldn't tell you the DTC's. P1201 maybe? The 7.3 is a little before my time, so when I get them here and there I kinda stumble my way through it. "KISS" and "back to the basics" have served me well on them Posted Image IMHO the documentation and published diagnostics for them is crap compared to the 6.0 and 6.4.

Bruce Amacker · September 21, 2009

The '94-'97 did not have the troublesome style screens, but rather a standard large inlet (window) screen on the bottom of the pickup. The Gen 2 trucks, 98.5-2003 did have the white plastic DTRM assy with the two screens inside.

Gen 1 screen with mechanical pump:

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