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I have a 7.3 power stroke that seems to run out of fuel at about 2800 rpm. If you let it shift it will pull strong up to that 2800 range and then flatten out. I have replaced the fuel filter. when I did I noticed that there was a part of an old filter in the bottom of the housing. I removed it along with cleaning out any sedement in the bottom of the housing. the fuel presure from the low presure pump is above the recomended minimums. I am not a diesel tech and have run out of ideas as to what to check next. This truck has 170k on the clock but has been well cared for. Just replaced the pan a month ago and there is still a cross hatch pattern on the cylinders.

check and see it it's a drive by wire. the tps is on the pedal. i've seen them flaten out and do just what you're talking about. check the turbo and see if the gate is opening. i've had a few where the exhaust was restricted. the throttle pedal if it's a drive by wire may not throw a code. it's easy to see with a scanner if it's working properly. another thing is to see if the harness has backed out of the injector module.

Goose wrote:I have a 7.3 power stroke that seems to run out of fuel at about 2800 rpm. If you let it shift it will pull strong up to that 2800 range and then flatten out. I have replaced the fuel filter. when I did I noticed that there was a part of an old filter in the bottom of the housing. I removed it along with cleaning out any sedement in the bottom of the housing. the fuel presure from the low presure pump is above the recomended minimums. I am not a diesel tech and have run out of ideas as to what to check next. This truck has 170k on the clock but has been well cared for. Just replaced the pan a month ago and there is still a cross hatch pattern on the cylinders.

I think redline on these isn't much past 3000. According to the power curve, max hp is obtained at 2600, so I wouldn't expect it to keep pulling after that.

Are you sure that the sediment was part of an old filter and not fragments from the inj o-rings? I know it sucks but I would get auth and check all the inj o-rings

It is starving for fuel. Definatly not at red line. The old filter had been replaced and the bottom of the Fram filter that was removed was in the bottom of the housing. That means that the junk that was in the old filter remained in the housing. Is there a screen in the housing that could be plugged or could any debris have made its way into the injectors?

Probally in to the injectors the only screen is the filter. How much debris was there?

There was quite a bit of sedement. Like a carburetor bowl that has sediment in the bottom. Funny thing is it runs great. Just seems to be lacking fuel. There is no missfire or rough running. You would think that if it had gone to the injectors that it would run rough or missfire on the injectors that got the junk in them. They all wouldn't get an equal dose.

I have had them lose the o-ring and only lack power. I found little pieces in the filter housing. I still think you should remove the injectors and check the o-rings on them. If you end up needing injectors(common) I buy alliant new ones. Alliant is who makes them for ford originally

where do I find Alliants web site? I read another thread on the forum and it indicated that someone on ebay had injectors that worked great and were reasonable.

yank an injector and take a good look before you repalce em all. there may or may not be contamination in the screen. does this have a banks kit in it? has it been scanned for pending codes? there may be a crack in the fuel line and it's sucking air when the injector pump calls for more fuel. i haven't seen any mention of a scanner reading. i hope that you're using one and not just making educated guesses. don't get me wrong, i know a lot of great techs that are experts on the particular vehicles they work on but get them away from that vehicle and they're lost. a bad throttle position sensor will not throw a code. the crank sensor acts the same way. another way you can direct your efforts is to spray wd40 or another type of nut buster into the air intake when it flattens out.

I agree you should watch the pids and get the fuel pressure readings but the debris in the ff housing is defintily a problem. The only problem?

the debris in the filter housing is where it belongs. it hasn't made it past the filter. lets say for example the truck had gasoline pumped into it's tank somewhere down the line. the pump may be showing the results of it being damaged. check pressure at injector. i think it's still an electronic issue. does it flatten out like it has a rev limiter or does it flatten out with that hollow roar a diesel makes when it's starving for fuel?

I have not had time to get back into it but did drive it Saturday and when it had run for only 3 to 4 minutes I was able to get 3100 rpm out of it. This leads me to beleive that the screen in the tank is part of the problem. My next move is to put a guage on the filter housing and drive it. Previously I hooked the guage in line right, after the pump, and power braked the truck. Acording to the diesel forum these tanks need to be cleaned at about 100k. This truck has 170k on the clock. I will have time Tuesday to dig deeper and will keep you updated as to the outcome. Thanks for the input.

checking the volume flow should give you the answer. what's the scanner telling you? try these two t.s.b's
03-21-42, 03-21-49. good luck...............

Problem solved! Pulled the tank today and took the pick-up of the line and took it apart. There is a large screen that sits on the bottom and inside the housing that it is attached to there are two smaller screens. They were filled with junk! Cleaned them out, cleaned the bottom of the tank and the rpm and power is all there. Thanks for all the input!