I am hoping that one of you can shed some light. Not REAL hopeful as I have stumped everyone I have asked but here goes.

I have a 2001 Duramax/Allison that was smoking but otherwise running fine. I ordered and installed a set of new Bosch NOZZLES. I did them one at a time, in a clean environment, making sure to reassemble with the same bodies, and spring packs. All gaskets, crush washers, and orings were replaced.

When I went to start after reassembly the motor will not fire. It wont even fart. It is not setting a code when I try to start it. I have checked the connections twice and all are tight and no pins bent or broken. I have disconnected the FPR to make sure it was allowing fuel through. I have disconnected the Crank sensor to see if it set a code and it does. I have gone over all the mechanical connections. There are no external leaks. There are no leaks under the upper valve covers. there is no fuel in the crankcase. I was running a kennedy diesel ECM and swapped back in the stock unit. Nothing, zero, zilch nada.

I disconnected the manifold heat and glow plugs and tried some starting fluid. It sorta started and finally set a 193 high pressure code. That would make sense if the engine was spinning at somewhere near idle speed but the injectors were not firing. At this point all I can think of is that I somehow shorted out the. fICM.

i don't think that it is the injectors that i rebuilt but at this point I am completely at a loss. How do I check the FICM and why did. gM not enable code setting from the unit? Any other bright ideas? Anyone want to buy the thing?

HELP!

 

Loss of prime,weak cp3 .... Possibly

 

Yeah could have been except the cp3 is less than 2 years old. Maybe some more info will help. I am running a FASS and the system is pre pressurizing to 9.5 lbs before I even crank. All of the O rings in the supply and return side were also replaced. Fuel filter has less than 1500 miles on it. I have fuel returning at the return line connection at the corner of the engine. Also. I can't see. it setting a 193 code if the co3 wasn't putting out the pressure. Keep the ideas coming guys!

 

Yeah could have been except the cp3 is less than 2 years old. Maybe some more info will help. I am running a FASS and the system is pre pressurizing to 9.5 lbs before I even crank. All of the O rings in the supply and return side were also replaced. Fuel filter has less than 1500 miles on it. I have fuel returning at the return line connection at the corner of the engine. Also. I can't see. it setting a 193 code if the co3 wasn't putting out the pressure. Keep the ideas coming guys! And as I said the truck ran fine prior to the tear down.

 

Fcim voltage or fuse ??

 

OK new territory. I did visually check the fuse but I have not checked anything at the FICM because I haven't got a clue what to do and where to do it. Can you outline the procedure, points I'm checking and anything else I need to know please? The last thing I want to do is fry something that isn't bad to start with. In the AM I'll actually put a continuity tester on the fuse and check to make sure I have voltage coming to it. Thanks for the help.

 

can't you get a friend to let you borrow their ficm, so you can test it in your truck

 

Dont have a friend with one within 900 miles. Besides that would be to easy!

 

Hate to say it but you might have to pull the injectors again. They should have pins that line up with holes in the nozzles and if you dont line them up and they seat properly they wont pop and atomize fuel. You can crank for ever and nothing will happen. Dont ask how I know. haha

 

Was aware of that so was careful when I put them back together. Please keep the ideas coming. Never did get a response to the procedure for checking the ficm. Also if someone can tell me if u can read voltage at the injector harness when cranking to know if they are firing?