Help with swap, won't start
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Help with swap, won't start I need help with lsx 5.3 swap. I did the harness myself and relay/fuse block as instructed on lt1 swap. I have power to all pink wires but I'm not getting power to fuel pump. I've tried starting with starting fluid and still it doesn't start. What could be the problem? I'm using a 6.0 harness and pcm. I got pcm programmed by Brendan at lt1swap.
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From: Ohio
You should hear it click, or the fuel pump prime. Get someone to turn the key while your head is either near the fuel pump relay or fuel pump. Should be pretty obvious even sitting in the driver's seat.
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One thing to check would be is to make sure right side coil wire harness is to the
right side coils on right side of the engine.
On one customer made harness, he put the odd side harness on the even side
coils, so the firing order was off.
But if your fuel pump relay is not getting a signal you need to figure that out.
I usually find if you use starting fluid, you will get some sign of life if everything
else is working. But I am far from being an expert. Good Luck
I went back and reread your first post and I guess missed the part that said no power to pump.
Last edited by slogo; Jan 6, 2017 at 11:49 PM.
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From: Whitinsville, MA
I had to do it when I got a mail-order tune for my truck.
Attempt to start the truck by turning the key to the Start/Run position. Try to crank the vehicle.
Observe that the vehicle fails to start and the security light is illuminated.
Release key to the ON/RUN position (not the ACC position or OFF)
Allow the vehicle to sit with key in the ON/RUN position for no less than 11 minutes. Security light will turn off after this.
When the light goes off, turn key to OFF position and allow the vehicle to remain in the OFF position for no less than 30 seconds.
Repeat #1-#5 for four cycles or until vehicle starts.
Attempt to start the truck by turning the key to the Start/Run position. Try to crank the vehicle.
Observe that the vehicle fails to start and the security light is illuminated.
Release key to the ON/RUN position (not the ACC position or OFF)
Allow the vehicle to sit with key in the ON/RUN position for no less than 11 minutes. Security light will turn off after this.
When the light goes off, turn key to OFF position and allow the vehicle to remain in the OFF position for no less than 30 seconds.
Repeat #1-#5 for four cycles or until vehicle starts.
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Thanks for the reply, I tried and no difference but I saw that one of my bulkhead wires wasn't hooked up to a constant 12v(I have a 86 squarebody chevy) so I hooked it up and bam it ran on starter fluid for a second. But I still have a problem I'm not getting power out of my fuel pump relay. What could cause this? Does the fuel pump relay have constant power output or just for a couple seconds if the engine isn't on?
Last edited by LunarNike; Jan 9, 2017 at 02:20 PM.
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Thanks for the reply, I tried and no difference but I saw that one of my bulkhead wires wasn't hooked up to a constant 12v(I have a 86 squarebody chevy) so I hooked it up and bam it ran on starter fluid for a second. But I still have a problem I'm not getting power out of my fuel pump relay. What could cause this? Does the fuel pump relay have constant power output or just for a couple seconds if the engine isn't on?