Our 2002 V10 Excursions do not have the PCV hose under the throttle body like in the video. The line comes out the right side of the throttle body where the casing is plastic. The fitting is the same old rubber 90 deg elbow, 17mmx9mm (3/4"x3/8"), but should be less prone to early failure from heat because it's not connected to hot metal. I couldn't find an aftermarket rubber 90 deg elbow, but there is a Dorman 46036 45 deg elbow with the same fittings as the OEM elbow. I used the 45 deg elbow, a straight brass 3/8" connector and 3/8" trans cooler hose to reroute the line further back to provide easier access to the COPs/injectors.

 

That's a good idea but only if fuel pumps were a known major issue, something needing frequent maintenance like spark plugs or filters.

Most F-Series owners will remove the bed---a lot less work in the end, less parts to disturb and replace. FWIW I'm driving two E-Series both with 200K + miles still on their original OEM pumps---not a bad track record IMHO.

 

Agree, but Ford made it MUCH easier to R&R lots of stuff. Heater cores for example.

My 79 bronco took the better part of a day to replace. My Ex wouldn't take but an hour or so.

If a fuel pump goes out its a complicated process which would require a good set of jacks and tools. If there were an access hatch, all that would be needed are basic hand tools and a little know how.

The older the Exs get the more likely a fuel pump will be needed.

 

Fuel pressure test was wonderfully inconclusive.

Key on - quickly up to about 30 psi

At idle - stays at 30 psi


Rev it up - Pops up around 35 and quickly back down

Put in gear and load with brake torque - comes up to about 35 briefly, then drops back to 30

Pressure holding - about 30 minutes after turning off it had dropped down to around 24psi

30-35 is on the low side, according to what I have seen in other posts. (my 2-volume, 15 pound FoMoCo Workshop Manual set does NOT have a spec. Instead it refers you to a separate Powertrain diagnostic manual. I was pretty happy about that.) But 30 is not the really low result you'd like to see to say that it is definitely the pump. I was able to make it die under that load, and the pressure never moved off 30.


Also, the suddenness of this issue doesn't match well with either fuel pump or clogged converter. You'd expect there to be some sputtering under heavy load first, that gradually gets worse. This was all well and good the last time I drove it, (and I hit the gas pretty hard on this, partly because it sits so much) and then the next time go to drive it, I can't pull forward at slow speed without it dying. That doesn't mean there can't be a sudden failure, but a sudden partial failure???


PCV looks ok, although mine is plumbed completely differently than the one in the video. Looks like they changed it due to that cracking issue.


Next will be some spark/boot/plug investigation. Not high on my suspect list, but I am going somewhat in order of cost. I don't want to have this thing towed somewhere for a new converter until I am sure that is the problem. (Same thing for dropping the tank!)


Does anyone know if there is any kind of backpressure test to check the converter?

 

Forgot to add - mileage is around 112K. New ignition parts were at 107K, but that was about 5 years ago. Like I said, it spends a lot of time sitting around contemplating it's grill emblem.

 

Wow I would have bet a dollar it was a fuel pump issue.

Sure there is no contaminate in tank?
You said it sits a lot maybe some water?
E85 maybe?
Try draining tank and putting new fuel in it.

If not my next step would be checking all vacuum hoses and putting a vacuum gauge on it.
Some overlook the information a simple vacuum gauge can give you. It can tell you if exhaust is plugged, or a verity of other issues.
Do a search for engine vacuum diagnosis, and you will see.

Do brakes "feel" ok? A vacuum leak on brake booster could cause a bad vacuum leak.

 

Yup... vacuum is on my list. If I did drain the tank, I'd just drop it and replace the pump. But condensation is not impossible. I never put any amount of "E" in it.


First I am going to rule out big ignition issues, since I have a spark tester and some extra boots.


Thanks again to all for the suggestions.

 

Here's a video about testing exhaust backpressure - Also, an article discussing backpressure - Exhaust Backpressure

I've had the CATs clog on 2 different vehicles. On an E350 the factory cat had the ceramic honeycomb break apart clogging the CAT and it wouldn't go over 30 mph. The replacement CAT had the ceramic honeycomb break up again into pieces and ended up in the back of the muffler. The car would still run, but it wouldn't go over 30 mph. The 460 is known for destroying CATs. Just pound on the shell and you can hear it rattling around inside. On a 2003 Expedition with 2 plugs misfiring the speed I could go slowly dropped from not going more than 65 mph up a steep hill, to only 60 mph up the hill, to finally around 35 mph around the block. I think the ceramic was melting or getting clogged. New CATs fixed the problems. There is a vacuum test that can be run to determine if there is a possible clogged exhaust. The CATs on the Expedition did not rattle, but when I ran a vacuum test it indicated a clogged exhaust.

 

Just did a search on the P0720 and P0722 codes.

Lots of info on this issue.

1st check alternator to make sure it's working correctly.
2nd clean battery terminals, and make sure battery is good.
3rd pull speed sensor on top side of extension housing and look for metal shavings. If found clean off shavings and reinstall.

Note shavings are not good.

I think your ignition system is weak due to a bad battery or alternator.
Try starting Ex and turn on all lights and accessories. See if problem get worse. If not it could be a short in wires going to speed sensor. I hope anyhow. If it is the shavings issue a trans rebuild may be needed.
Is your OD light flashing on gear selector?