Please bear with me. I'm not a mechanic, and I'm not going to be working on the truck myself. I can change oil and just learned how to change the starter, but that is the outer limit of what I can do. However, I've spent a small fortune on the truck in the last few months and I've run out of discretionary cash to spend. The problem is that my 7.3L 2000 truck has begun to lose significant amounts of power while towing my 26' alumalite travel trailer. I'm doing 40 mph on easy grades. Here is the sequence of events, starting with what immediately preceded the start of the power loss:

In August last year, I started blowing smoke and had to have the PCM replaced. I didn't immediately notice a problem after that, but I didn't have a lot of hills to travel from Ohio to PA. Leaving PA, I noticed the power drop-off and as soon as I landed, I took the truck in. Mechanics diagnosed it with a dirty fuel filter. Changed that and the air filter and fixed an exhaust leak. A month later, I left Louisiana and headed for Fl. On Florida "hills," I continued to get no more than 50 mph. Took it in again and was told that the strainer in the tank was probably clogged, so they dropped the tank, replaced the strainer, checked to see if the fuel was dirty, replaced the fan clutch, and sent me on my way. A couple of weeks later, whirring in the rear sent me back to the shop for pinion bearings. Heading north out of Florida, I was still experiencing power loss on the "hills," so I brought it to a dealership in Gainesville, where they replaced the fuel pump. I did notice a slight improvement in responsiveness on surface roads and without the trailer, but as soon as I hooked the trailer up again, I began dropping power on the hills. Going through Alabama, I stopped for diesel, and for about a half an hour, I had normal power and was charging up hills. Then it faded away and went back to slogging up the hills at 40 mph. I'm currently in Tennessee, and I'm frantic. I've spent several thousand dollars on this problem, and it still isn't fixed. There is no smoke, it isn't throwing codes, there are no vibrations or lurching, and I hear no unusual sounds coming from the engine. I've asked mechanics to consider the turbo, but they swear it's fine, despite a minor oil leak around the hoses.

My first thoughts are turbo (still, and despite assurances to the otherwise), uncalibrated PCM, injector pump. Others have suggested the tranny (torque converter) may be going or a partially clogged fuel line.

So....thoughts?

 

Hang tight, there will be a bunch of knowledge chiming in to help you! There are a lot of people on here that really know their $h!+ about these trucks! (unfortunately I'm not one of them)! But am learning a lot from them!

 

Check the boots on the intercooler. Let us know.

 

Subcribing

 

The engine needs a good supply of fuel, high pressure oil (to drive the injectors) and air to make sufficient power. It sounds like the fuel sysyem is pretty well covered with the repairs you had done to the tank, filter and pump. Insufficient air could be the problem, but usually produces some smoke from what I understand. There are a number of potential problems with the high pressure oil system that might be causing your trouble, including an intermitent pressure sensor or regulator.

In any case, it's really necesary to check the engine performance with a diagnostic monitor while driving. That will help pinpoint what is happening when you lose power and avoid replacing the wrong parts. Did any of the mechanics that serviced the truck monitor the engine with a scanner while driving? If not, maybe someone on here can recommend a good shop that's close to you.

Wish I could be of more help, but I'm just learning the basics of these engines myself.

 

You know the more I think about this, it still sounds like fuel. Check under neat the truck for a pinched fuel line. Maybe the dealer got the fuel line in between the frame and when you need more fuel under a load it can't keep up. Lot of guys with this problem once they do the inside tank mods don't have anymore problems.

Chet

 

Welcome to FTE. When they changed the strainers in the fuel tank, did they clean out the fuel tank? Did they replace the screens in the mixing chamber or just clean the screen on the pick up foot?

Can you tell us more about the exhaust leak they fixed? Was it the up pipes that were leaking at the collector behind the turbo? Can you look to see if there are lots of soot stains coming from around the work they did now?

Does your problem happen all the time, or just when you're at 1/4 tank or less? Does the truck sound any differently or just not go? I agree in checking the hose clamps on the CAC boots, but that shouldn't slow you down to 40, just give you worse MPG's and a bit of low power.

What part of Tennessee are you in? If you're close to Nashville, take it to the guys at Swamps diesel in La Vergne. They know more about the 7.3 than all the mechanics you've seen to date put together. They will at least be able to diagnose it for you if you don't have the funds to fix it now.

 

Thanks for all the quick replies. The clamps on the hoses appear tight. Chris, according to the mechanic that did the strainer, the fuel in the tank wasn't particularly dirty. (I was smart enough to ask the question.) I don't know about the multiple screens. I THINK he did the mixing chamber screen, but I don't know for sure. (I wasn't knowledgeable enough to ask THAT question.) I remember him saying something about two types of screens, so maybe? I do know I never heard him use the term mixing chamber. :-/

The exhaust leak was right at the manifold/turbo connection, according to the mechanics. I don't know if it is still leaking, although I know I have another leak in the compartment. I'm not real sure where. There is soot on the firewall, but that was there from the original repair.

The problem happens all the time, and it never sounds any different.

I am in Smyrna, TN....and I think La Vergne is actually not to far from me. I may check that out. Thanks.

 

Swamps can help you for sure. Not a bad place to start.

Chet

 

hopefully, Swamps will be the end, and not the start. I have to wait until I unload the truck to take it in. It's full of stock and work stuff. I may not get it in until next week, so in the meanwhile, if anyone else wants to take a stab at troubleshooting, have at it.

 

Search boost-leak detector. Do you have a boost gauge?

 

A good fuel pressure gauge would tell you the story when going up that hill. Its just strange that when you filled up that one time it ran great for a while. I mean its not running rough is it, just lack of power.

Chet

 

not running rough at all. Everyone that listens to it agrees that it is purring like a kitten. Starts right up, no smoke, no rough idle...but as soon as the trailer is hooked to it and we're heading up a hill, it's a dog. A sleeping dog. A lame sleeping dog. I have no tools or instruments to read anything....boost or otherwise. I know I'm not much help to you guys, but there it is. I did once suggest a boost leak to a mechanic, only to have him shake his head. Maybe it's because I'm a girl. I dunno. I guess I was just hoping someone had had the exact same problem and had repaired the same components and had found a solution. I'll be taking it into Swamp's Diesel as soon as I get all my work stuff out of it...I can always come back and post the resolution of the problem, IF it is resolved.

 

From your description it sounds like a fuel restriction.

Swamps doesn't just work on diesel motors. They customize and build all things imaginable that has to do with the 7.3 Powerstroke. Most people deal with Swamps if they want to upgrade their engine. Just fixing yours back to where it runs stock will be no problem for them, although they might try to talk to you about some upgrades you could do to make the truck even better.

The good news is they won't treat you any different because you're a girl. Just tell them the guys on the forums said Swamps was the best and tell them everything you can about what your history has been. Just be sure to post back with the resolution.

I do all the work on my truck(s), but I would let swamps turn wrenches on mine. They know what they're doing.

 

I'm thinking MAYBE a stuck IPR (Injection Pressure Regulator)... explains the no smoke and being intermittent. Won't know until you get a scan too on it and read live data. If you're going to Swamps, they WILL tell you what it is. These are good trucks and will run a long time and be trouble-free IF they get put in the hands of a good mechanic. Guys who know what they're doing when it comes to these trucks are hard to find. Swamps will definitely fix you up, just watch it... they're gonna get you on the mod wagon and it's hard to stop (see signature)!