The Build: 2001 ECSB Silverado 2500HD "SS"

juddski88

Freedom Diesel
Jul 1, 2008
4,656
120
63
Chesterfield, Mass.
ok, I have a short somewhere. I have a blown ecm fuse under the hood and my class 2 wires in the ecm test positive for continuity when grounded. I can't load a tune and It wont crank. (not cranking might be another issue with the ignition switch itself not being clocked properly, Ill check it tomorrow)
 

juddski88

Freedom Diesel
Jul 1, 2008
4,656
120
63
Chesterfield, Mass.
fixed my starter issue, another mistake by me, i had put the lever of the solenoid on the wrong side of the spring! learned quite a bit about the difference between this starter and the old style though in the process...

so now the truck is not building rail pressure when cranking. I unplugged the RPS to max it out and still not building enough actual pressure. its basically 0. I tested return lines to see if i had stuck injectors or a bad cp3....nothing...so i test cp3 return, nothing....i tested with and without the RPS plugged in. nothing...so I make sure my MITUSA is actually pumping fuel while cranking...nope. however, when i pressurize the system with an air gun at the filler neck, fuel blows right past the pump. so it shouldn't be restricting flow to the gear pump of the cp3 that much that it wouldnt start, no? My only two thoughts are either the RPS is bad, even though unplugging it didnt help...or I have a crap, brand new cp3 from II. unless I could have an injector stuck open? not sure here. need some advice.
 

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,715
779
113
Texas!!!
Try unplugging the regulator and see what happens. I don't think unplugging the rail pressure sensor will make it build max rail pressure.
 

xcablb7

New member
Feb 8, 2009
536
0
0
Fall River
I was talking to a guy with a dodge at ts and he had a belt drive pump similar to a mitusa, he had several issues priming it so he put another electric pump before it and has had no issues since, and it holds full lift pressure on the dyno or through a pull
 

juddski88

Freedom Diesel
Jul 1, 2008
4,656
120
63
Chesterfield, Mass.
That was the first thing I tried actually. I'm going to try an electric pump before the mitusa I guess to see but the gear pump on the cp3 should also be creating suction right?

Try unplugging the regulator and see what happens. I don't think unplugging the rail pressure sensor will make it build max rail pressure.
 

GMC_2002_Dmax

The Still Master
The CP3 should suck through the MITUSA regardless of whether the pump will create pressure.

If you removed the stock filter head you lost any ability to prime up to the filter.

A small lift pump would work, I have a single Laing Pump left here, no Carter's so let me know if you want to buy that Laing and I'll ship it out to you.

Tony
 

juddski88

Freedom Diesel
Jul 1, 2008
4,656
120
63
Chesterfield, Mass.
Congrats on getting it running :thumb: what do you have left to do to finish it up?

A lot. Needs the coolant tank mounted, water pump and plumbing installed, shock mounts for rear, find short in CAN wire to tcm, exhaust needs finishing, lights arent done, also needs a frame to house computers inside. guages, datalogger, fuseblock, boost controller, and ill mount the MITUSA back on to see if i fixed the leak.
 

juddski88

Freedom Diesel
Jul 1, 2008
4,656
120
63
Chesterfield, Mass.
My conclusion is that the wiring job to relocate the computer(s) is well worth the time and is pretty straight forward. Same goes for running LLY and LBZ injectors with LB7 ECM and FICM. Tuning may prove to be a pain in the arse, but o well.