Yeah I know. What I can't find is what pins are where on the actual connector. Every other connector is on there like, for the FICM and every single sensor but the ECM is not
02 LB7 Crank no start
- Thread starter Fryerdiesel
- Start date
That doesn't matter now anyway because I have a crank signal and RPM but what I would like to know is what the circle of broken lines means around both the crank and cam sensors. I guess it means shielded wires but I also can't find where S170 and S171 are located on the truck.
The connectors are labeled. Small numbers molded into the connector
Yes, shielding
Oh ok Thanks! Now I know.
So, if it's making white "smoke" from the exhaust that actually is fuel vapor because it smells really strong like raw fuel when I crank it, doesn't that mean the injectors are firing?
White smoke is raw unburnt fuel. That is not good because it could mean the injectors are leaking.
Yep, raw unburnt fuel. Off the top of my head for potential reasons, leaking injectors, very low compression, really cold, or timing is way off like a sheared crank pin
Should be able to see which ones are leaking, if so by removing all the glow plugs, pull the EDU fuse and crank it over. If none leak then put the fuse back in and recrank an all eight should spray fuel mist out the flow plug holes
Compression test when the glow plugs are already out
Inspect crank balance pin depending on above results
Crank pin and the tooth wheel inside there are both good because I checked them. This is a real head scratcher because all it did was sit for a while so even though the compression and injector tests are logical, it still doesn't make sense why a perfectly good running truck would not start just from sitting but, I guess I'll be buying a diesel compression tester...
I've absolutely seen material plug an injector while sitting, either from being suspended in fuel/created by the pump or just water causing rust/growth etc so it is possible in my opinion.
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Okay I have a dumb question. I assume you mean ECU fuse when you say EDU but when I look in the box, I don't see which one that is.
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Also, the 2 fuses directly under 1 and 2 are not even on the truck but, when I looked at my other (running) LB7 truck, it doesn't have them either. So, they obviously don't matter but why are they even on the fuse schematic?
I forget your's is an 02 Duramax. The wiring was weird for the pre 03 years. The 03+ calls the FICM fuse EDU. Your's I think is fuse #1 for injB
Okay, thanks I'll pull that one and see what happens.
Okay, I don't know what the hell is going on. Pulled the 25A fuse 1* for INJB and fuel still sprays from the holes. Then, I took out 1,2,3 and 4. Same thing. Finally I pulled the 10A ENG 1 and the 20A ECM B also and it still sprays from the glow plug holes! So, does it take a few cranks to dry out after fuel is injected? I don't understand it.
The one on the driver's side rear does seem to be putting out more fuel than the rest I guess because fuel is dripping down the firewall but I can't really tell for sure
A few seconds of cranking should dray out most of the fuel in any cylinder. If it continues to pump out fuel mist, you either have leaking injectors or the FICM is still active. Maybe just pull the harness connectors right off the FICM if you're not sure on the fuse
A few seconds of cranking? Okay I probably didn't crank it long enough
Well this time I did the compression test on all the cylinders so it definitely cranked long enough and I pulled 6 fuses plus the fuel pump relay just to be sure I disabled the fuel system and I definitely got sprayed by at least 2 cylinders. One of them is really bad. 
I also posted the numbers I got on the compression test but I can't believe I have bad injectors with the FASS pump that has 2 fuel filters and those injectors only have about 40k on them. This sucks... NOT looking forward to this job! I guess all 8 should be replaced right