OK everyone i have read a lot on here replaced a lot of parts on the truck and the issues are still here.


its a 1997 powerstroke with a little over 300k
it wont start unless its plug in
it wont go over 2000 rpm when cold
when it does warm up i can floor the exalerator and it hesitates and then slowly picks up
i have replaced all glowplug
replaced gp relay
replaced valve cover gasket
internal wiring harnes for gp and injectors(it helped a little)
replaced fuel filter
checked fuel presure its great
check and changed oil and filter
replaced both batteries


what else should i check i am at a loss

 

How is the engines compression?
300K is getting up there.

 

Have you watched the oil discharge cold with the valve covers off? Performed a Buzz test? Sounds like worn injectors IMO.

 

Moved to the 1994.5 - 1997 7.3L Power Stroke Diesel forum.

 

Hi Alex, Welcome to FTE!

I am going to take a swing at it and say that you have either an injector o-ring that is blown or you are having IPR issues. Either way I think low HPO pressure would confirm either one. Do you have access to a scanner or a gauge you could put on the HPO system to see what kind of pressures you're running?

Do you have any trouble re-starting it when it is warm? Was the fuel filter black when you changed it? Have you noticed any oil consumption?

An easy way to check the blowby is to remove the oil filler cap, turn it upside down and set it on top the fill port. If it just kinda rattles there you're probably in pretty good shape compression wise, if it blows off of there, well then.... you have a lot of blowby. That means nothing is cheap from there on out.

 

X2 ^^^^^^^^^^^

 

so what you guys are saying is if the oil fill cap plows off then my motor is basicaly just a big boat anchor? i have notice that when trying to start it there is smoke in the engine compartment but i think thats from an exhaust leak by my the turbo. once i do get it started and warmed up it pulls just fine. i drive it to work and there is a 6% hill thats 5 miles long and it will do 70+ up this hill and it hardly even smokes. i would think if i had bad injectors then it would smoke a lot. right?


i pulled the valve covers off and tested all the glow plugs. they all get red hot in just a second or two.



and one more thing what and were is the IPR?

 

one more think when i pulled my intake off to get to the gp i noticed that there is a little bit of oil in there. and some on the turbo fins. is that normal or it that a sign that i have a lot of plow by.

 

You are correct on the testing procedure. But I wouldn't say the engine is a boat anchor. If it blows off the valve cover then you have a lot of blow by which indicates worn rings. You can rebuild the engine if you want to, or just live with it. I honestly don't think the blowby issue is your problem. The oil in the intake is normal. There is a PVC of sorts there that vents into the turbo inlet so the oil vapors end up making things a little oily there in the intake.

You didn't answer the rest of the questions in my above post. I say this not to be a pain, but because the answers can lead us to the root cause of your issue. The IPR is a spool valve that threads into the back of the high pressure oil pump. It controls the High Pressure Oil pressure to the injectors which really affects fueling. Blown IPR o-rings can create this issue but most often the telltale sign of bad IPR o-rings is a hard warm start.

Here is a picture of where it is located and a picture of the IPR itself.





Another thing you can do is to unplug the ICP sensor (also shown in the drawing above) and see if there is any oil in the connector. If there is that means the ICP is bad, but I don't think this is your issue since you said the truck runs good once it is warmed up. Easy thing to check though.

 

ok once the truck starts for the first time in the day it will start up just fine after that

 

When you first start it in the morning do it feel like it only running on 5-6 cylinders and missing and sputtering when you try to give it the go pedal?

 

yes and when trying to start it without it pluged in it knocks really hard on at least one maybe two cylinders.

what i do not get is it only has to be plugged in for about 30 minutes and it will start right up even when the outside temp is below 20 30 minutes is not long enough to warm up the engine

 

I think you have worn poppet valves in the injectors

 

so i need to get a new set of injectors? or is this something i can get a rebuild kit for?

 

You can have them rebuilt by Rosewood diesel