Hello. I have a 2001 F250 XLT v10. Truck has 445,000 miles on it and i know im on borrowed time as it is but had a baby recently and can't afford a new one right now. This truck has never had problems but about a week ago about halfway on my hour trip to work she started to bog down on anything other than slight acceleration. Made it to work and started going through the forums trying to figure out the problem. Knew my air filter was pretty dirty so I swapped that out and threw a fuel pressure gauge on her. Starts fine and gives me 30psi at idle which I'm told is correct. Figured maybe fuel filter so I also swapped that out even though there was only 10k on it. Got in it to go home and halfway home again started acting up. She's still drivable but I sure wouldn't wanna merge onto a highway right now. Starts perfect and runs good for about 30 minutes but at the same spot the last few days on a hill she starts to bog down and seems to get worse the longer I go. I have about 100k on my fuel pump so that's my next swap but I'm looking for some advice. I've never has a fuel pump "going bad" they always are either good or bad. Also I have no codes and I have checked multiple times with my scanner. Any advice would be greatly appreciated.

 

Crud in the tank?

 

1-Drive with "fuel pressure gauge " attached (and visible to you ) few days and monitor it when the truck is acting up. I have heard fuel pump acting like this when going south .

2- Post it in V-10 forum for better exposure .

Good luck

 

Plugged/bad catalytic converter?

 

This^^^^ if those are the original cats I bet that's your problem

 

I once had marginal plugs and wires cause the same symptoms, acted exactly like fuel pressure/filter problems and all tests at idle were fine.

If you are at the point of pulling your tank to check for crud with no other evidence, I would change plugs and wires first. Particularly if fuel pressure at the rails is good when it happens.

Clean the MAF before that? Cheaper and quicker than plugs and wires, but not quite matching your description.

I'm shotgunning more than diagnosing.

ETA: I have not heard of the cats plugging suddenly so I question that being the root cause; you report "sudden" onset. My problem did get worse for a couple weeks, but was a "sudden" onset. The more I demanded of my engine, and the higher the speed I demanded it perform, the more it acted like it was starving for gas. It was starving for spark.

 

I've had one set of cats do the "gradual degrade" because of misfires that took me awhile to figure out.
Another vehicle had a "sudden onset" plugged exhaust when the honeycomb broke into pieces and collected at the end of the muffler. Rapping the cat produced no rattle, but the muffler rattled when I finally figured it out.
There's a vacuum test I found online that will help rule out a clogged exhaust.

 

445,000 miles are lots for a catalytic converter. I would check coolant temperature sensor that may be telling computer motor is hot and detune it. At 445,000 miles it could be any number of things. I have seen wires that get hot and disconnect inside and when they cool off make connection inside again.
Congrats on new baby. Boy or Girl?

 

I have a 00 5.4 v8, I am in need of a new exhaust. Is there any tests that can be done to tell if the cat is still performing properly or if it is starting to get plugged?

 

disconnect them and drive it. If the problem goes away then they probably are clogged. You should get a CEL with clogged cats though

 

To the OP,
do you have torque pro? I went through a similar problem on my v10 excursion that I chased for a few weeks. I ended up using the misfire monitor in torque pro to find the problem. Not all scanners can access/interpret the mode $06 data. In torque pro add the "send obd command" button in the realtime information section (touch and hold screen, add display, push button, send obd command) once you add the button, touch and hold the button and select display configuration, then set command to send. The command you want to put in is "0653" this will bring up the mode $06 data.
Scroll through until you see the misfire monitor. It is all in hexadecimal code, so it's not going to jump out and smack you,you'll have to scroll through it. I don't remember what the exact code is, but it will end with a 0 through 9, all in order. 0 should be cylinder 10, all others match with the number.
monitor this when it bogs down and see if one cylinder (or multiples) are misfiring.

a single cylinder could likely be narrowed down to spark, multiples it's not as likely, but still a possibility. The COPs like to fail without notice, and usually with temp swings.

 

I agree, but mine did not.
Our 2003 5.4L Exped has a dual exhaust and I think one side was clogged.
Higher RPM under load (hills) and it was losing power.
It had misfires from rain leaking onto #6 & #7 which I could feel, but didn't always set codes.
There was a vacuum test when accelerating I found online that indicated a clogged exhaust, but I don't remember the specifics.
I've seen on ebay an exhaust pressure test gauge for under $25 that looked interesting. It plugs into an O2 port to measure the exhaust pressure.

 

Good point. I didn't think about dual exhaust

 

I have had a catalytic converter "suddenly" clog up. The ceramic matrix inside of it fractured. Loose ceramic chunks rearranged themselves to block the exhaust flow.

Also, no, I didn't get a CEL.