LS Swap
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FloridaLife
SILVER Star
BP???
Yep
BP automotive makes great harnesses, but I agree with the other guys that may not be the issue
FloridaLife
SILVER Star
FYI, it will crank for a couple of seconds, then nothing. Below is a short video. Any suggestions appreciated:
Video of Gen 3 LS crank
Video of Gen 3 LS crank
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We gave suggestions well i didn't but i agree with @onemanarmy . What ecm do you have is it out of a donor vehicle did it come with a kit has it been flashed or tuned do you what passlock is and that it needs to be turned off in the ecm.?
I had the same issue. the computer needs to be flashed to remove the VATS or whatever its called.
FloridaLife
SILVER Star
The engine, a stock 5.3 LM7 (truck LS), 4L60E transmission, and ECM all came out of a donor vehicle. The numbers in front of the passenger's side head show the engine is a 2002. The seller, and that's all he does for a living is buy 15 at a time from a salvage yard he has a relationship with, flashed the ECM and asked me questions like gear ratio and tire size before he did it.
FloridaLife
SILVER Star
The guy working on my 40 had a friend come by and plug into it and it shows the VATS are off.
interesting....a 2002 would be 'passlock' I believe?
if all of the anti theft is indeed flashed out, then I'm at a loss
if all of the anti theft is indeed flashed out, then I'm at a loss
FloridaLife
SILVER Star
And, it is not reading the TPS at all. Swapped it out, and it is still not reading it. The guy working on my 40 even tried holding the throttle at various positions and it still didn't read anything. He is starting to think the wiring harness might be the issue. And he's restored lots of 40's and done lots of SBC swaps, but this LS swap is a first for both of us, so we are not LS wizards.
Do you have power when key is on ? Do you have keyed power while cranking?
FloridaLife
SILVER Star
Yes. And now he's got it where it will fire up every time, but only runs for about 3 seconds and then dies.
May have missed it, is this drive by wire or cable?
the DBW has a separate harness/brain for the pedal/throttle control. Do you have that? (if needed)
the DBW has a separate harness/brain for the pedal/throttle control. Do you have that? (if needed)
Thst old should be cable driven but good question
I've got a mid-2002 Suburban drivetrain that was DBW
its a transition year across the board
its a transition year across the board
FloridaLife
SILVER Star
It is cable.
Ok. I'm out!
FloridaLife
SILVER Star
It was originally drive by wire, but we switched it to cable for the FJ40. And the harness is for a cable TPS. The ECM was stock and flashed.