I purchased a 2000 excursion with the 7.3 a couple of weeks ago. The guy said originally in the add that it need #2 and #8 injectors replaced. When I went and looked at it he had already replaced them and said the it still has no power and needed the remaining 6 replaced. I purchased it as it was a good deal thinking I should be able to get it fixed for worst case a set of injectors. BTW the engine has little to no blowby and starts easy and idles great. The problem it it will not build any boost (has external boost gauge). Actually the gauge only shows vacuum. With the truck in park or neutral you can slowly rev the motor to 2500rpm and all seems fine but as soon as you break past 2500rpm it sound like it is missing and starts blowing white smoke. The smoke smells like when a diesel heater runs out of diesel. If you try and drive it it has NO power and will not move out of its own way and will eventually start like it is missing and blowing white smoke.

The previous owner replaced the following:
#2 injector
#8 injector
UVC gaskets
MAP Sensor
Wastegate solenoid sensor


The first thing I did was start looking at the no boost issue and pulled the turbo. I deleted the EBPV while i was there. Also the turbine wheel was in very bad shape so i replaced the turbine wheel, shaft, seals, bushings and installed a new compressor wheel 5+5 wheel off ebay. Reinstalled turbo and the symptoms are the same. I also replaced the clamps on the spider with Tbolt clamps instead of the worm gear styles and it psi tested all piping and intercooler to 30psi with no leaks. Also the up pipes have already been replaced with the bellowed style so there are no leaks and it has a 4" straight exhaust.

I have since ordered oring kits for the injectors and also ordered the fittings for the fuel bowl so i can check fuel pressure. it has a new air filter, oil filter, oil and fuel filter installed.

The ICP sensor has oil in the plug but if i unplug it the symptoms are still there.

I have also used a scanner and the ICP pressure is approx 500psi at idle and the duty cycle is about 11% at idle. Also the HPOP looks to be new as it is very clean compared to the surrounding parts and i have checked the HPOP reservoir and it is full to withing 1/2" from the threads.

I will check fuel pressure by the weekend as the fitting will be here Thrusday but does anyone have any suggestions? i have read a few threads of what seemed to be this exact problem but no one ever posted their fix.

Thanks for the help.

2000 Excursion
7.3
205000 miles

I am assuming that the injectors are original other than #2 and #8.

 

I think your on right track with fuel pressure. No fuel = no boost, power. Could be as simple as clogged filter or in tank screens

 

I 2nd the thoughts on a fuel supply issue. I have seen a couple of posts describe what you are seeing and a new fuel pump fixed it. Although, the in tank filters may be causing you problems as well.

 

Yeah Im really thinking/hoping its a fuel delivery problem. At first the white smoke was confusing me as it is usually it is raw fuel but I guess if the fuel pressure is low then the spray pattern from the injector isnt correct causing the fuel not to burn causing the white smoke.

 

Almost ALL of these trucks need the in-tank and pre-pump mods by now. The issue is the non-serviceable filters inside the tank.

The good news is this only costs $20 if you DIY!!!

 

Well I hooked my fuel psi tester down at the pump tonight since my adapters won't be here until tomorrow to be able to test psi at the filter housing. The psi came up to about 50psi within a couple seconds of turning on the key. Once I started it it came up to 60psi. After a couple of seconds it dropped to about 30psi for just a second but came right back up to 60psi. I could rev it until it would start running bad and it would hold 60psi pretty steady. I'll upload a video when I get it off my phone. My adapters will be here tomorrow to be able to check psi at the filter housing but I'd say this rules out a pump or clogged filter in tank. I'm still planning on doing the hutch mod but I don't think that is my current problem. The Icp sensor plug does have oil in it so I'm going to order a new one just for good measure.

Any suggestions?

 

Check the fuel filter. Bypass the tank and run it off a 5gal gas can. See if the the pressure remains steady at 55psig or more. If not I would invest in a new pump and try again.

 

That's the thing it held at 55 or higher. Only dropped for a split second then held like a rock. I did notice that when I cycled the key the pump would sound like it was getting air in it even though the psi was pretty steady. Also the fuel filter is new.

trying to upload the video to YouTube so I can post a link.

 

Just Brain Storming....

Have you performed both a KOEO / KOER Test?
Contribution Test?
Injector Buzz Test?
Fuel regulator Valve for Restriction?
Verify that MAP hose is not damaged, plugged or pinched?
Verify that intercooler hoses or intake are not leaking.
Verify that the green Wastegate hose is not plugged.
Monitor MGP (manifold gauge pressure) and RP?
FUEL PW: 1 MS - 6 MS? (<1 / >6 IDM Suspect)
The MAT? (Manifold Air Temperature) the PCM uses this signal to adjust fuel and timing.
VFD (Volume Fuel Desired) and MFD (Mass Fuel Desired)? Comparing these two is critical for a Performance Issue.

That's about all I can think of at 01:30 Hours!

 

Fuel level in the tank is above 1/4? You can attach a hose to the discharge on your fuel bowl drain over on the passenger's side front, near the EBP tube. Then you can run the fuel pump and see how it's flowing through the filter. Of course you want to feed that into a bucket of some sort.

 

Tank is 3/4 full. I will have the adapter today to be able to check psi at the filter housing but now I'm not to hopeful that it will be this simple of a fix.

As as for the koer, koeo, contribution and all other tests mentioned above I have performed them all and they all passed other than cyl 8 on the contribution but I read that is fairly common. I will have the scanner again their weekend so I can monitor it again but all the readings were within that I can remember.

is there anything else in the filter housing that could cause a fuel delivery problem other than the main filter which I just replaced?

 

Also pirschwagon what are you referring to as RP?

 

There is the pressure regulator that sits inside of that housing on the top of the bowl towards the driver's side. There's a spring and a poppet in there that I believe releases fuel and pressure back to the tank via the return line, which comes out of that housing. I do not know if they fail without some 'user assistance'. If you open the drain valve on the fuel bowl and turn the key on you can see if fuel is running through to bowl. The outlet for that is a steel tube the dumps out near the EBP tube at the exhaust manifold. I just did mine yesterday and did it through the wheel well with a large vinyl tube and five gallon bucket.

 

there is also a check ball inside filter housing inside the center stand pipe.

 

In addition, if the plastic safety/shut off valve should be lined up correctly. You can see the valve in the picture below.




There are slots in the pieces of plastic that should be lined up. This is a quick and free check to perform.

EDIT: Ipzd beat me by 1 minute... but I have pictures included