[LS Swap] Didn't Start :(
Thread Starter
Race Director
Joined: Dec 2005
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From: Fisher, IL
[LS Swap] Didn't Start :(
Well after months I finally turned the key tonight to try and start my LS1 in my '69
I know it's going to be very hard for most to offer help troubleshooting since it's so unique but figured if anyone had any pointers on where to start it might help.
Fuel pump worked.
turn the key with clutch pushed in and nothing. Nothing tried to turn over or click. The MIL(check engine light) comes on and stays on while the key is in Run but it's not showing any codes or issues.(I might try to fiddle with the settings on my OBDII scanner to see if it's in the wrong mode or something)
I guess I'll start by multimetering my ignition power stuff again making sure i have hot in RUN and Crank.
I know it's going to be very hard for most to offer help troubleshooting since it's so unique but figured if anyone had any pointers on where to start it might help.
Fuel pump worked.
turn the key with clutch pushed in and nothing. Nothing tried to turn over or click. The MIL(check engine light) comes on and stays on while the key is in Run but it's not showing any codes or issues.(I might try to fiddle with the settings on my OBDII scanner to see if it's in the wrong mode or something)
I guess I'll start by multimetering my ignition power stuff again making sure i have hot in RUN and Crank.
Thread Starter
Race Director
Joined: Dec 2005
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From: Fisher, IL
I'll double check my wiring grounds. I know I hooked up the battery ground but forgot the #1 body mount clip on ground. Wonder if that would do it?
I can't think of any other frame grounds off hand.
Drifting
Joined: Oct 2008
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From: springfield ohio
You should have a battery to frame ground, and a frame to motor ground. The original frame to motor ground is off the motor mount frame horn and bolts to the block. You will need this for the starter to turn over along with the starter circuit being correct thru the Ecu unless you wired the system differently.
Riggs
Riggs
Thread Starter
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From: Fisher, IL
You should have a battery to frame ground, and a frame to motor ground. The original frame to motor ground is off the motor mount frame horn and bolts to the block. You will need this for the starter to turn over along with the starter circuit being correct thru the Ecu unless you wired the system differently.
Riggs
Riggs
I'll have to search my basement but I have a feeling it left with the engine when I sold it.
What gauge was that? 2?
Just bolt it anywhere to the motor?
Thread Starter
Race Director
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From: Fisher, IL
I have a 4gauge ground wire from a sound system I haven't installed yet.
From what I remember that seems to be about the size as the old ground(which looks like it got sold with the old motor)
any best place to ground to the motor on the LS1?
From what I remember that seems to be about the size as the old ground(which looks like it got sold with the old motor)
any best place to ground to the motor on the LS1?
Thread Starter
Race Director
Joined: Dec 2005
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From: Fisher, IL
LOL. I have a photo of just it in my alblum for some strange reason.
Not sure why I would have sold it with the motor but I'm not seeing it in my stuff so I'll look a bit more then just use the 4gauge from the audio stuff.
Not sure why I would have sold it with the motor but I'm not seeing it in my stuff so I'll look a bit more then just use the 4gauge from the audio stuff.
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Burning Brakes
Joined: Oct 2008
Posts: 1,037
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From: Mobile Alabama
Man what a bummer!
Grounds are one the biggest problems with LS swaps, you cant have too many. With a fiberglass car it is even more important. I am guessing your PSI harness is not tied into your original starting circuit, so trouble shooting no cranking would be the same as for an original C3.
Grounds are one the biggest problems with LS swaps, you cant have too many. With a fiberglass car it is even more important. I am guessing your PSI harness is not tied into your original starting circuit, so trouble shooting no cranking would be the same as for an original C3.
Thread Starter
Race Director
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From: Fisher, IL
Man what a bummer!
Grounds are one the biggest problems with LS swaps, you cant have too many. With a fiberglass car it is even more important. I am guessing your PSI harness is not tied into your original starting circuit, so trouble shooting no cranking would be the same as for an original C3.
Grounds are one the biggest problems with LS swaps, you cant have too many. With a fiberglass car it is even more important. I am guessing your PSI harness is not tied into your original starting circuit, so trouble shooting no cranking would be the same as for an original C3.
I don't see it not starting too bad a thing. I had 2 fuel line leaks that I was able to spot that would have been a bit dangerous if it had fired up right away.
I think you're right. I didn't change anything with the starter from the stock ignition. Only difference was the old solenoid had 4 wires going to it and the LS1 has 3(no wire to the distributor) right?
So I have a feeling it's not related to the PSI harness as I would have thought it would try to crank the other day when the computer wasn't even plugged in.
Pretty sure I put the purple wire to the small post on the LS1, and the others went to the 12v large post... the ground post was already grounded to the motor. Any tips with troubleshooting figuring out if the starter is right?
Last edited by PUNISHER VETTE; Oct 27, 2012 at 11:01 PM.
Burning Brakes
Joined: Oct 2008
Posts: 1,037
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From: Mobile Alabama
You can always jump 12v to the solenoid to see if it will turn over. Check for voltage at the purple wire S terminal with key in start position - 12v but no start = bad ground or starter solenoid and/or starter. No 12v = switches or wiring or fuse or connections in the start circuit.
Drifting
Joined: Oct 2008
Posts: 1,496
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From: springfield ohio
If you had you harness redone, there should have been wires that were meant to run to your ignition, not the starter, although you should still be able to turn the motor over providing the starter circuit is complete.
Riggs
Riggs
Thread Starter
Race Director
Joined: Dec 2005
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From: Fisher, IL
You can always jump 12v to the solenoid to see if it will turn over. Check for voltage at the purple wire S terminal with key in start position - 12v but no start = bad ground or starter solenoid and/or starter. No 12v = switches or wiring or fuse or connections in the start circuit.
I'll test in the morning.Actually the guy in the video made me feel smart when it comes to this and we all know I'm not the best mechanic lol.
I think i had my tiny solenoid wires reversed on my old 350 motor a while back because they aren't the same color as they used to be. I have a feeling I'm not getting 12v to the small post...
Thread Starter
Race Director
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From: Fisher, IL
I think it's something with the old wiring screwing me up but we'll see.
Thread Starter
Race Director
Joined: Dec 2005
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From: Fisher, IL
Not sure what would happen if they screwed up some of the computer settings but I'm sure if it's their business they surely don't mess up all that often....
