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My LB7/LLY build

stacks04 said:
white smoke is probably from all the fuel from the endless cranking prior to. the crank stop crank stop, could be a lot of things. check all grounds, and hook both batteries up. these engines are tough to crank on 2 batteries let alone 1. did you re bleed the system after you had it running? maybe you have a loose line or something sucking air and it took 20 mins to get air bound again.
Click to expand...

yea could be, didn't bleed the system after until it died. I'll hook another battery up and loosen some fuel lines, try to let some air out again.
Thanks stacks.
 
ok just went out there this morning tried to turn over, same thing but my radio clock reset to 12:00 like I disconnected the battery and re-connected it, it seems to do that everytime I try to crank, battery voltage was showing 12v on cluster, I'm sure it's pretty close with efilive logging as well.
That is what stumps me, something kills the battery, gonna put on the second one now.
 
ok hookeed up a battery that is not in great condition and it already seems better, gonna buy a new one, let em charge for 10 minutes or so and see what happens.
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Good luck man. I've been following this thread. Sounds like your right there on the verge of having it going. Keep up the good work!
 
ok battery on, MUCH better, letting it charge now. Still kinda cuts out, can't tell if fuel delivery is cutting out or if starter is cutting out, just got the starter yesterday, from autozone.I wish you guys could hear it.....will see if I can figure out how to upload a video/audio
 
Got a BUNCH like maybe 10 codes all U1000 Class 2 Data Link
2 TCM requesting MIL


main fuel flow rate2 from -512 to 72.5 average of 98.1

timing 0.0-4.0 avg of 1.7

actual fuel rail pressure avg. 2803 / desired 6092

coolant 79*

RPM average of 36, 233 max

is that class 2 data link code , a lost comm with ECM??
 
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could be. post the code nums and let me do some digging. are they repeat codes? meaning they are the same ones everytime.
 
It is DEFINETLY something electrical, I wiggled the TCM and ECM wiring and checked codes, No U1000, truck is REALLY trying to crank, it bumps over like it wants to.
I have a copy of GM's service manual and am in the process of looking up in it the procedures for a DTC U1000, but I have no Tech 2. There are a lot of modules that communicate on the CAN-BUS system/Class 2 serial data network, something is not communicating allowing it to crank. Either ECM or TCM. It is so much closer to cranking, I'm almost giddy inside.
When I lowered the engine in the motor kinda sat on the TCM wiring, but wifey seen it and I immediately moved it. I have checked TCM wiring and it seems fine.. man I wish I had a spare ECM, this one has always had a loose connection.........................
 
I'm gonna be the post king by the time this is done, just wanna keep you guys updated so no one is searching in the wrong direction. I SINCERELY appreciate all you guys helping out, I'm gonna out alot of people dinner and a beer..or 2 or 12.

ok,
I disconnected the TCM completely, truck did exact same, almost cranking.
checked the codes with TCM disconnected and have:

Code: Module:
U1000 Body Control Module
U1000 Instrument Panel Cluster
U1000 Transfer Case

hooked TCM back up, cleared codes, didn't come back. Tried to crank, same. disconnected EFILive, reconnected, tried to crank, same. Checked codes ....NO U1000
 
I FOUND THIS:

It is common for the leaf contacts and/or the resistor pellet on the key bow to become contaminated to the point where the VATS decoder module cannot correctly sense the pellet resistance, or cannot sense any resistance at all. This would usually cause a no crank/no start situation. Cleaning the key pellet and leaf contacts can frequently restore system operation. Because of the risk of contamination and other reasons, NO liquid lubricants should ever be used on the ignition lock cylinder. The generally accepted lubricant for ANY lock cylinder, whether a plate or pin type mechanism, is powdered graphite ONLY. This especially applies to VATS ignition lock cylinders.

It is also common for the two wires from the ignition lock cylinder contacts to break due to the necessary flexing which occurs every time the ignition lock is moved. This can usually be diagnosed by measuring key pellet resistance at the VATS module or at the connector at the base of the steering column.

There is a small two-wire connector in the upper bowl of the steering column which can become damaged or disconnected as well, since clearance between moving parts in the upper column bowl are minimal.

The connector at the base of the steering column can fail if subjected to stress, moisture, or movement if the lower bolster trim is not in place.

The connector at the VATS decoder module is generally reliable, and the connection at the start enable relay is also relatively safe from interference and reliable. However, all connections should be checked when diagnosing the system since any connection can fail or add resistance to the circuits. The start enable relay itself is a mechanical device, and can fail after prolonged use.
 
have you checked the ficm fuse. it is num 25 under hood. also there is 3 grounds on the lower right side of the engine block. triple check those. for the ficm. and ecm.
 
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