When i run the cylinder contrubution test. The truck is a late 99 has 319,000 i put glow plugs, and gaskets/harness and injectors, fuel lift pump last year . Performance stuff is 4 inch, wicked wheel,six gun stacked with preditor k&n fipk, BTS valve body crank case vent mod, hpop cross over line. I have also put the recall cam position sensor .along with oil temp,exhast back pressure sensor and tube, high pressure oil sensor, and all high pressure oil line and fittings. Lots of money in the last year. Now the issue . It has lost power and i run the cct test and it says #4 is 3.5 to 5.0 then today it was #1 went to 6.0 then jump to 2.0. #3,#5,#7 always around 0 the others #2,#4 are low like 1.0 . What concerns me is the boost is still there 27 lbs. but it seems to have more power at halfe throttle than full makes more boost but less power. I changed fuel filter today and pulled the covers no wires out of place. I used a solus scan tool no codes and passed the buzz and contrubution test . I Have today pulled a bad Injector driver control bad code with my Preditor. Whats your thought s on the pc going bad ???? Sorry for the run on snap on says one thing and Preditor says another. any ideas

 

What Temp you did contribution test always same temperature engine if not this cause bad reading,are you change oil.I change two injector 4 and 6 and after i changed still i pull code for 6.After 50 miles maybe 100 contribution test pass sucesufull.I change cps sensor on my other van and i have right now on 1st injector.

 

Regardless of codes, if you have more power at half throttle than full throttle that usually means your HPOP is not keeping up. What injectors did you use- single shot or split shot? I doubt it has anything to do with low fuel pressure, or your boost would fall off at the higher RPM, not maintain or a bit higher. what codes specifically are you pulling?

 

Fresh oil less than 500 miles on it also test was done after 30 min of warm up. It seems to have lost power and has a miss at idle. I think i may try to get my hands on an injector and see if i can get #4 down. Also if you have one bad can it cause the others to move around on the preditor. The solus is not mine a buddy loans it to me. It has the boost but no power and seems not to smoke like it used to . I wonder if it could be fuel intanke filter and one bad injsector , any ideas i am open

 

I used split shot all where AD1831551c1 i purchased them from Diesel care and performance. so they where reman. the contribution test is what concerns me what is normal my 5 and 6 are 0.0 ths is stupid but would a low compresion issue cause it to change around more than an injector. I am going to try to check the hpop pressure this week end. If it was hpop would that not be the same as no fuel. Low oil pressure bad atomization , inturn not as much fuel are not good easy burn fuel . Give me some guys that run into the hpop problem what was there other symptoms because i have been thinking of changing it but dang they are salty, thanks ps codes dont remember the numbers will get them but i do remember the idm (injector driver comes up alot) i have checked and rechecked wires and nothing.

 

The gray CPS is known to cause high readings on the CCT, specifically on #8 and IIRC, #3. If you have one or can find one, try the black one and see if the readings are more normal.

 

What codes.When you change injector you need drive 50 miles no oil in the rail and injector swaping bad.Give some time dont do anything help us what codes thank you.

 

Pmbmax, I agree, you need to get that bad injector changed out.
I went through the exact same thing as you when I put a set of rebuilts in.
#4 injector CC test was 15% rpm drop according to the Predator and the stick shift would wobble on fast idle.
To make a long story short I ended up buying a full set of new Alliants, now everything is good.
.
Also don't discount fuel pressure just yet. You need to verify that the fuel pump is keeping up with demand. Attach a gauge with a long hose to the fuel rail, temporarily, then go out and WOT accellorate up a hill.
It needs to stay at a minumum 45 psi and that's borderline. I like to see 55-60 at all times.

 

What do you guys see with the gray cps on the preditor on the % change . I am trying to get a injector also who has a compresion tester that will work for a 7.3 that is cheap and good or good for the money. I have one and it hits the pushrods. Thanks guys

 

P1316 was what was in it from when i drove to town and back. This time is shows #4 #8 to be 4 %

 

This is not big problem.Loose UVCH connector under valve cover but you have to find which side.Here's what the problem looks likehttps://www.ford-trucks.com/forums/801882-2001-7-3l-f350-service-engine-soon-truck-shakes.html

 

Thats what i also thought i pulled the covers uesterday to see if anything was out of wack. All plugs look like they did a year ago when i put them on. I even found a washer that i could use as a shim to use as a lock to keep them from coming apart in the future. I did find one glow plug that was showing open so i replaced it(#3). I have looked at all the wires and why does it seem to change . I wish i had ainjector driver to put on it but i am the only guy in my group that dont drive a dodge. If i have to put an engine in it anytime it will be the c word. Thanks any other ideas keep them coming.

 

I am slow on some stuff what does this mean and IIRC, #3.

 

truck driving bad or some symptoms i think irc its injector 3

 

Turn the key on (don't start) and measure the voltage from the center pin to a good ground. Is it more or less than 1 volt? If it's more, you need to ohm the injectors on that side (key off). If you need to know how to ohm the injectors through the wiring connector let me know. If it's less than 1 volt, not the color of the center wire, then find that same color wire going into the back of the 42 pin connector (square box with a bolt going through it just above the drivers side valve cover. If you remove the bolt, you can check for continuity or resistance across that wire. Make sure to inspect the wiring closely right behind the square box to see if there is any sign of chaffed wires. If possible, have someone wiggle the wiring harness while you have the meter on it to see if anything shows up. If that checks out good, note the pin location, then the color of the wire coming out the other side of the 42 pin connector. You'll need to check that wire back to the IDM. These wires have been known to chaff against the drivers side valve cover, so check that as well.

It may be easier to skip the 42 pin connector for now and just check the wire from the valve cover all the way back to the IDM. It shows the center pin on the valve cover traces back to pin #23 on the IDM connector (which should be up above the wheel well liner on the drivers side.
Attached Images 2000 E series IDM pin out.pdf (21.4 KB, 6 views) https://www.ford-trucks.com/forums/8...elp-p1670.html