DIY fuel kill switch
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Joined: Jan 2007
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From: Wa
DIY fuel kill switch
Looking for some info for a DIY fuel kill switch. I couldn't find anything using the search and want to do this and if there is no DIY I can write one up,but I want to gather some info on how to correctly do this before I start. anyone have any tips or thoughts?
I have done this on my other cars (all hondas) and I did ti by simply hooking a switch inline with my fuel pump power wire, but I don't know if this will work with my sc, since I believe the fuel pump wiring is way more complex then on a old school crx. any input is great.
I have done this on my other cars (all hondas) and I did ti by simply hooking a switch inline with my fuel pump power wire, but I don't know if this will work with my sc, since I believe the fuel pump wiring is way more complex then on a old school crx. any input is great.
I've always wired in a relay on the positive power side to the fuel pump for this sort of thing... this allows a low amperage wire to be run to a smaller, remotely mounted switch that can be placed almost anywhere...
I can draw you a diagram later if ya'd like...
I can draw you a diagram later if ya'd like...
Thread Starter
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Joined: Jan 2007
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From: Wa
Hrm, so could you draw me a diagram, this si good info but I don't want to risk something. I will write up a diy or something if I can successfully do this. What exactly is the purpose of the relay? would using a 30a switch need a relay?
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From: Wa
bump, woudl a relay really be needed if i wanted to tap a 30A switch onto the fuel pump power wire? Where is the ecu for the fuel pump. Man these cars aare way more complicated then my old crx...I wish there was an online service manual or something.. :P
Thread Starter
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Joined: Jan 2007
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From: Wa
I don't care about the cost of a relay, i just don't know the purpose, and how a relay will make the wiring any easier. I just got this car and don't have any wiring diagrams so i don't know where to look.
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you don't want to splice into the wires to run a pair of wires all the way from the PCM or from the fuel pump ECU to a remote location - voltage drop and such is an issue... thats the purpose of the relay - to not have to worry about voltage drop over an extended length of wiring...
we've been doing it this way in the talons for YEARS, and it is the only way to keep the correct voltage...
we've been doing it this way in the talons for YEARS, and it is the only way to keep the correct voltage...
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if you want wiring diagram, it's super simple...
at the fuel pump, there are two wires, green and white/black... white/black is ground and green is power (variable, I might add, from the fuel pump ecu)... at the fuel pump ecu, you have green (power out to the pump), white/black (ground), black/red (+12v battery power), then pink and red/green both go to the PCM... what I would do is cut battery power at the black/red wire going to the fuel pump ecu...
at the fuel pump, there are two wires, green and white/black... white/black is ground and green is power (variable, I might add, from the fuel pump ecu)... at the fuel pump ecu, you have green (power out to the pump), white/black (ground), black/red (+12v battery power), then pink and red/green both go to the PCM... what I would do is cut battery power at the black/red wire going to the fuel pump ecu...
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From: Simi Valley ,CA
When doing a kill switch never tell anybody where it is wired to or you are defeating the purpose... Plus the fuel pump is the first place a thief looks ,there are many other places to tap in, but keep it a secret.
Thread Starter
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From: Wa
SWEEt thanks for the diagram. On my other car I had just put a switch inline , no relays, but now I understand why it'd be a good idea to have one. not many theives are going to rip up the interior to find the fuel pump though, and if you hid the wires in a loom so it looks stock, then most won't notice it. Thanks though I'm going to do this and let you know how it works!
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