Sudden loss of power- inconsistent symptoms

[Wire89]

Here’s a photo of the filter, bowl, and fuel. The filter has about 5000 miles on it.

A related question, it looks like the drain lever is actually connected to a cable. Is that true, to assist in fully opening? If so, where’s the other end? Can trace it.

[Wire89]

Originally Posted by Wire89

A related question, it looks like the drain lever is actually connected to a cable. Is that true, to assist in fully opening? If so, where’s the other end? Can trace it.

Well never mind on that cable question. Found it right next the tranny dip stick, labeled and everything.

[Bbasso]

Doesn't appear to be dirty in the least.
But I would change since you're this far.

[clark]

Yeah, bummer, looks fine. Maybe time to measure fuel pressure?

[Wire89]

Originally Posted by clark

Yeah, bummer, looks fine. Maybe time to measure fuel pressure?

Yep. Any suggestions on a quality electric fuel gauge and sender so I can mount in the cab? Might as well do it now that I have access to the fuel bowl ports.

[clark]

I used : Fuel Pressure 0-100 PSI EV² - Riffraff Diesel Performance Make sure to get : Pressure Port Adapter - 90 deg elbow x 1/8 FNPT for Ford 7.3L (99-03) - GZ-13-002 as well.

RiffRaff is my favorite place for 7.3 stuff.

This is where the can of worms is opened. You'll want to remove the fuel bowl to install the fitting (I did mine post filter, port on passenger side. I had a tiny leak at the newly installed fitting so I got to remove the fuel bowl twice!) Since you have the bowl out you might as well change all the orings unless this has been done- kit available from RiffRaff of course.

[Wire89]

Sorry for the long delay here...got a pressure gauge installed and new filter. I went with the Autometer 0-100 gauge plus the isspro snubber kit. I used the pre-filter port without a 90* elbow as I was able to get the whole kit installed from the doghouse side without removing the fuel bowl, though had to remove the resonator box. Everything back together and wired up, I’m getting a pressure of 52 psi. Ran out of time so haven’t been able to see what pressure does when the power starts to drop on a grade. Will test tomorrow.

[Wire89]

Ok....just cruising around town the pressure will stay between 47 and 52. Accelerating into the highway it dropped to 40 quickly, then to around 35. As I get to cruising speed the pressure will build back up to 50. On the grade that I’ve testing this issue on the pressure drops to 20’s as long as I remain at higher rpm trying to gain speed, then will slowly drop all the way zero. It remained at zero for approx 1 mile to the top of the grade, at which point the pressure will back towards 50. So far, after two runs, the original issue has not repeated itself.

I’m guessing if I stayed at zero longer is when I’d get that sudden loss of power, and then decelerating allows the pressure to build, making it possible to accelerate again. Obviously fuel pump? Or look elsewhere first? Thanks all.

[bet on black]

If that's the pressure readings pre-filter, then I would look to the fuel system prior to that for issues.


I would start with looking in the tank. Make sure the fuel pick up isn't clogged or damaged.

Some people have successfully cleared a clogged line by shooting compressed air back through the feed line to the fuel pump from the fuel tank. The junk is still in the tank; so this really isn't a long term fix.

Check fuel pump wiring for damaged wires, or bad connections.

If everything checks out, try changing the fuel pump then, as it may be the culprit. Also trace all fuel lines prior to where you tied in the gauge sender to make sure it's not pinched somewhere, causing a restriction.

[arctictraveller]

This seems to be a comon problem lately.

http://www.sportsmobileforum.com/for...tml#post225592