LS Swap Retuned - Engine won’t start

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born2Run83

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1983
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GMC - C1500
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5.3L LM7
Swapped in a 5.3L LM7. Engine was tuned by tuner and ran great. While still running great (and not knocking) the Check engine light came on - I read the code and showed to be knock sensor. He sent me another tune file to upload via RTD+ through the TDN App on my iPad. Uploaded tune. Now engine cranks but will not start. Any ideas??
 

Nasty-LSX

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did you copy the tune before you wrote the new one? If so, put it back in and see if it starts. if it does, the tune he sent is bad
 

Nasty-LSX

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What was the outcome?
 

born2Run83

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I apologize for the late reply. I Wrote Full Tune again with the tune he sent recently. I don’t recall having a copy of the original. There is one there that says “Restore” though, perhaps that is it? I have a new battery now, the previous battery was old and I attempted a few Writes on it prior to hooking up a charger, I didn’t think it’d take that many attempts. Hopefully that did not “brick” The pcm? I’m still learning about this quite a bit..
 

RecklessWOT

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350 TBI
Man how convenient. The super complicated computer setup on a TBI is impossible to troubleshoot, and carburetors are straight up old fashioned, not sure anyone can even put up with driving a truck with such stone age technology. I hear an LS swaps makes the truck more driveable and easier to live with day-to-day than dealing with an old fashioned carb or TBI setup. Is your LS super fast? At least it's gotta be real nice to drive everywhere right? :p

Hope it was worth it :waytogo:
 

newguy11

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Man how convenient. The super complicated computer setup on a TBI is impossible to troubleshoot, and carburetors are straight up old fashioned, not sure anyone can even put up with driving a truck with such stone age technology. I hear an LS swaps makes the truck more driveable and easier to live with day-to-day than dealing with an old fashioned carb or TBI setup. Is your LS super fast? At least it's gotta be real nice to drive everywhere right? :p

Hope it was worth it :waytogo:

Ouch.
 

born2Run83

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5.3L LM7
Man how convenient. The super complicated computer setup on a TBI is impossible to troubleshoot, and carburetors are straight up old fashioned, not sure anyone can even put up with driving a truck with such stone age technology. I hear an LS swaps makes the truck more driveable and easier to live with day-to-day than dealing with an old fashioned carb or TBI setup. Is your LS super fast? At least it's gotta be real nice to drive everywhere right? :p

Hope it was worth it :waytogo:
LMAO! Ah heck it’s just money right??
 

BrianCarroll

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c-10 sport
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5.3 LS swap
1979 short bed SPORT ls swapped 5.3 ls truck kicks butt.
a few issues engine back fires upon deceleration.could be broken ex man bolt leaking.
presently has sm465 factory truck four speed with granny.
\But ovet thanksgiving picked up a m21 Muncie car trans 4 speed.
All I can say about your dash gages is this :
LS swap requires ecu unit voltage to gauges is wrong so none of mine worked I had to step down the voltage with a resistor to get them to work Factory tach still wrong so I need one more resistor.
Be sure you have a good ground to the cluster that makes things goofy.
 

born2Run83

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1979 short bed SPORT ls swapped 5.3 ls truck kicks butt.
a few issues engine back fires upon deceleration.could be broken ex man bolt leaking.
presently has sm465 factory truck four speed with granny.
\But ovet thanksgiving picked up a m21 Muncie car trans 4 speed.
All I can say about your dash gages is this :
LS swap requires ecu unit voltage to gauges is wrong so none of mine worked I had to step down the voltage with a resistor to get them to work Factory tach still wrong so I need one more resistor.
Be sure you have a good ground to the cluster that makes things goofy.
Thank you Brian! Sounds like you have a solid truck with that 5.3! As far as my gauges go, I have the dakota digital setup and changed the resistor etc for the LS ECU so everything there is good to go.
 

RecklessWOT

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LMAO! Ah heck it’s just money right??
Haha, sorry man I may or may not have had a few drinks last night, my bad. Glad you didn't take it personal.

Hope you get it figured out soon, that does suck. Obviously I'm no LS expert, but there's a handful of people on here who have done that to their trucks, someone should be able to give you pointers. Good luck!
 

born2Run83

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Haha, sorry man I may or may not have had a few drinks last night, my bad. Glad you didn't take it personal.

Hope you get it figured out soon, that does suck. Obviously I'm no LS expert, but there's a handful of people on here who have done that to their trucks, someone should be able to give you pointers. Good luck!
All good!! gotta have some fun right!? otherwise whats the point lol.

I have a few options here with the tune/pcm. Hoping one works out soon. It drives nice when it's all lined up and working right haha
 

Bextreme04

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All good!! gotta have some fun right!? otherwise whats the point lol.

I have a few options here with the tune/pcm. Hoping one works out soon. It drives nice when it's all lined up and working right haha
It sounds an aweful lot like either the tune didn't load right or maybe the tuner left on the VATS.
 

Bextreme04

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If you can read the .bin file off of it, maybe someone here could take a quick look. If you have a generic OBD2 device, you should be able to read a .bin file off of it using LSDroid or PCMhammer
 

Camar068

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If you can read the .bin file off of it, maybe someone here could take a quick look. If you have a generic OBD2 device, you should be able to read a .bin file off of it using LSDroid or PCMhammer
good to know, thx
 

born2Run83

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P0601 code- bad pcm
 
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