fuel pump hotwire upgrade kit - how does the pcm know?
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fuel pump hotwire upgrade kit - how does the pcm know?
I have a fuel pump hotwire upgrade kit, apparently designed to give more voltage to the fuel pump. Here's a short description:
"this kit is designed to install into your LT1 powered F body GM car and is designed to overcome the losses associated with factory wiring to the fuel pump. Because of the heavy 12 gage feed, sealed relay and attachment to the output stud of the alternator, extra voltage and current become available to the fuel pump, increasing both fuel volume and pressure during WOT, when it’s needed most."
Which is fine, sounds like you just plug the three-wire connector in at the back of the car (purple, grey, black wire), and attach the red ring terminal to the back of the alternator.
What I am not understanding is this...the PCM has a dark green with white stripe wire coming out of it that is the FUEL PUMP RELAY CONTROL. If you install the upgrade kit, how does the PCM know how to control the fuel pump/relay???
Here is a diagram of what I'm talking about:
And here is a pic of the fuel pump hotwire upgrade kit:
Also, I am assuming that big relay in that kit is the NEW fuel pump relay, and the stock one is ignored. If someone could confirm that I could rest easy.
Thanks for any help and clarification.
"this kit is designed to install into your LT1 powered F body GM car and is designed to overcome the losses associated with factory wiring to the fuel pump. Because of the heavy 12 gage feed, sealed relay and attachment to the output stud of the alternator, extra voltage and current become available to the fuel pump, increasing both fuel volume and pressure during WOT, when it’s needed most."
Which is fine, sounds like you just plug the three-wire connector in at the back of the car (purple, grey, black wire), and attach the red ring terminal to the back of the alternator.
What I am not understanding is this...the PCM has a dark green with white stripe wire coming out of it that is the FUEL PUMP RELAY CONTROL. If you install the upgrade kit, how does the PCM know how to control the fuel pump/relay???
Here is a diagram of what I'm talking about:
And here is a pic of the fuel pump hotwire upgrade kit:
Also, I am assuming that big relay in that kit is the NEW fuel pump relay, and the stock one is ignored. If someone could confirm that I could rest easy.
Thanks for any help and clarification.
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Gotcha, thanks toretto. Makes sense. After doing some more research, the big black bulkhead connector on the upgrade kit goes into a connector that has wires that go to the Instrument Panel Wiring Harness, so it does connect to the factory wiring. I didn't know what that bulkhead was for before.
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This is good information.
I just ordered mine.
https://ls1tech.com/forums/lsx-parts...ump-setup.html
It will be nice to have a piece of mind.
I just ordered mine.
https://ls1tech.com/forums/lsx-parts...ump-setup.html
It will be nice to have a piece of mind.
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I just ordered my hot wire kit and pump on Saturday.
It should be here by Wed or Thurs. I can't wait to get it.
I ended up buying it from a member at BMR Fabrication.
It just happend to be someone that works there getting rid of thier
own personal kit. Listed in the parts classified section.
I would have purchased the kit from Lonnie's Performance otherwise.
Lonnie is a fuel specialist and a sponsor that helps everyone posting the Fueling section of LS1Tech.
You can always contact Lonnie, he has those kits in stock.
It should be here by Wed or Thurs. I can't wait to get it.
I ended up buying it from a member at BMR Fabrication.
It just happend to be someone that works there getting rid of thier
own personal kit. Listed in the parts classified section.
I would have purchased the kit from Lonnie's Performance otherwise.
Lonnie is a fuel specialist and a sponsor that helps everyone posting the Fueling section of LS1Tech.
You can always contact Lonnie, he has those kits in stock.