The correct way to make a Fuel pump Cut-off switch!! Tech Article

Post by **driftin8ez** » Fri Dec 15, 2006 8:39 am

This mod is a good security feature as well as a helpfull diagnostic tool. If your car is having trouble starting you can use a fuel pump kill to see if it is getting to much fuel and flooding out. Also if hidden it makes a great anti-theft device.

What you need:

Tools:10mm socketFlat and Phillips head screw driversSoldiering Iron Wire stripper/cutter

Materials:14 or 16 gauge wire ( i used speaker wire as it is really two wires making it easier to fish around your interior)Solder and shrink wrap tubing (best method)or at the leastCrimp connectors and electrical tape (ok method)Toggle switchDouble sided tape to stick the switch somewhere hidden

--1)V

Locate your car. Hopefully it is where you left it the night before. After this mod you can sleep easier.

--2)VLocate and remove interior panels by passenger side right foot well. (s13 pictured, S14 may differ slightly)

--3)VLocate ecm and remove the 10mm bolts holding it to the chassis. Remove harness from ecm with the 10mm bolt and refer to diagrams to find fuel pump relay wire.

==== ====

==== ========

--4)VIn most cases the fuel pump relay wire is b/p or black with a purple stripe. Cut the wire about 6 inches from the ecm. Then connect the two 14 or 16 gauge wires one to each end of the cut fuel pump relay wire.

--5)VNow run this wire under the dashboard to the driver side foot well. Connect your toggle switch to the two wires. Hide the switch in a creative spot. Start the car with the switch on. It should start and idle normal. Flip the switch off and the idle should start to bog down as the engine starves of fuel. If your switch works correctly your done! Bolt you ecm back in and fasten all the interior panels back together. Hide the wires as best you can and Job complete.

Modified by driftin8ez at 4:55 PM 12/17/2006

Modified by driftin8ez at 11:33 AM 1/3/2007
Modified by driftin8ez at 5:03 PM 3/31/2008

Post by **MagikDragon** » Fri Dec 15, 2006 8:56 am

Great Write Up!! 2 thumbs up!

Post by **skylinekin** » Fri Dec 15, 2006 8:58 am

sweeettt, i am going to do this right now, thanks!

Post by **AZhitman** » Fri Dec 15, 2006 9:06 am

BRILLIANT!

Sweet article, this is going on http://www.240sxTech.com.

Let me know what you want your "custom title" to be!

Post by **AZhitman** » Fri Dec 15, 2006 9:13 am

Done.

Custom title = the tag under your screen name.

Post by **driftin8ez** » Fri Dec 15, 2006 9:16 am

AZhitman wrote:Done.

Custom title = the tag under your screen name.

Ohhh lol... There i go again. Let me think about that one.Thanks for the name change as well.

Post by **rico05** » Fri Dec 15, 2006 10:31 am

Nice. If my dash wasn't littered with random switches already, I would totally do this.

BTW, glad you kept your car Its hella nice.

Fri Dec 15, 2006 10:39 am

got the ecu diagram for sr? btw, nice write up

Post by **driftin8ez** » Fri Dec 15, 2006 12:54 pm

adrians_s13 wrote:got the ecu diagram for sr? btw, nice write up

I'll try and locate one but I'm not really to fond of the SR so i don't have the fsm or anything.

AZhitman wrote:Done.

Custom title = the tag under your screen name.

AZhitman my custom title will be = Jersey's Finest

Post by **Driftless240** » Fri Dec 15, 2006 10:36 pm

Man wants his Custom Title !!

Post by **sochinkyeyesshut** » Sat Dec 16, 2006 12:55 am

: i second that diagram for an ESSSSSSS ARRRRRRRRGGGHHHHHHH

Post by **asher4857** » Sat Dec 16, 2006 2:57 am

ive been wanting to do a few kill switches in my car for a while now. this wont hurt the engine will it? like.. if i do this everytime i shut the engine off?

Post by **driftin8ez** » Sat Dec 16, 2006 4:55 am

well if you do it like this the engine will never know. Turn the engine off then flip the switch off. Turn the switch on then the engine .

Post by **asher4857** » Sat Dec 16, 2006 5:19 am

lol.. good point..

Post by **Dookie** » Sat Dec 16, 2006 5:57 am

sochinkyeyesshut wrote:: i second that diagram for an ESSSSSSS ARRRRRRRRGGGHHHHHHH

There are plenty on the internet, search for it

Post by **IHeartTurbo** » Sat Dec 16, 2006 7:08 am

It would be better, safer, and easier to put the switch on the ground wire coming out of the fuel pump

Post by **lenso** » Sat Dec 16, 2006 7:55 am

sochinkyeyesshut wrote:: i second that diagram for an ESSSSSSS ARRRRRRRRGGGHHHHHHH

here you go. red top pinout is 104 color is b/p

Post by **adrianfromthecastle** » Sat Dec 16, 2006 8:37 am

lenso wrote:

here you go. red top pinout is 104 color is b/p

thanks bro!

driftin8ez wrote:I'll try and locate one but I'm not really to fond of the SR

eh... whatever.btw... email greg for the title. he'll get back to you in like an instant

Post by **driftin8ez** » Sun Dec 17, 2006 11:48 am

IHeartTurbo wrote:It would be better, safer, and easier to put the switch on the ground wire coming out of the fuel pump

You lose. Again this is THE BEST way of doing it. It doesn't mess with the stock power circuit of the fuel pump. It only controls the relay which controls the circuit.

lenso wrote:

here you go. red top pinout is 104 color is b/p

Thank you i will add this to the original post.

Post by **le_ryan** » Sun Dec 17, 2006 12:04 pm

not bad dood, I pulled my article, yours is much better.

Post by **driftin8ez** » Sun Dec 17, 2006 7:12 pm

vroom-chirp wrote:not bad dood, I pulled my article, yours is much better.

Thank you Thank you

Post by **skylinekin** » Thu Dec 21, 2006 6:19 pm

when i leave my car sitting for a few hours with the kill switch on, i flip the switch off and try to start my car and it takes alot longer than normal to start, does this happen to anyone else?? did I do something wrong?? I followed your directions, i have a SOHC and I spliced it in the b/p wire.

Post by **Drewster** » Thu Dec 21, 2006 8:49 pm

let the fuel pump prime first

Post by **skylinekin** » Fri Dec 22, 2006 8:17 am

it never did this before i put in the switch though.

Post by **S3t0_S13** » Fri Dec 22, 2006 9:00 am

dont just turn on the car immediatly, turn the key to start, (when the windows go up and down, jeez i forgot that position) give it a couple seconds so the fuel runs in the lines and then start her up, mine used 2 do that 2

GREAT write up by the way man, love it

Post by **skylinekin** » Fri Dec 22, 2006 10:56 am

alright, thanks.

Post by **driftin8ez** » Fri Dec 22, 2006 6:58 pm

skylinekin wrote:when i leave my car sitting for a few hours with the kill switch on, i flip the switch off and try to start my car and it takes alot longer than normal to start, does this happen to anyone else?? did I do something wrong?? I followed your directions, i have a SOHC and I spliced it in the b/p wire.

If you turn your car off then flip the switch to kill the pump. Then come back and flip the pump switch so the pump will turn on before you put the key in, then turn on the car it should have no effect on starting. If you put your key in turn it to on then flip the switch it wont prime the fuel system and give you a longer start. The pump runs for about 3-5 seconds after you turn the key to the on position so if you still have the pump killed it wont prime.

Post by **SirSilvia** » Fri Dec 22, 2006 7:30 pm

skylinekin wrote:when i leave my car sitting for a few hours with the kill switch on, i flip the switch off and try to start my car and it takes alot longer than normal to start, does this happen to anyone else?? did I do something wrong?? I followed your directions, i have a SOHC and I spliced it in the b/p wire.

well yeah once the engine sucks the fuel outta the line (when you flip the switch off) The pump has to send fuel through a partialy empty line therefore taking longer.

Post by **driftin8ez** » Sat Dec 23, 2006 8:05 pm

SirSilvia wrote:well yeah once the engine sucks the fuel outta the line (when you flip the switch off) The pump has to send fuel through a partialy empty line therefore taking longer.

Correct but you should flip the switch after the engine has completely stopped spinning, and flip the pump back on before even putting the key in to have a seamless and closest to stock functionality.

Post by **ca18datsun510** » Sat Dec 23, 2006 8:48 pm

so using speaker wire and duct tape is the correct way to do this?

The correct way to make a Fuel pump Cut-off switch!! Tech Article

The correct way to make a Fuel pump Cut-off switch!! Tech Article

Re: The correct way to make a Fuel pump Cut-off ... (driftin8nez)

Re: The correct way to make a Fuel pump Cut-off ... (MagikDragon)

Re: (AZhitman)

Re: The correct way to make a Fuel pump Cut-off ... (driftin8ez)

Re: The correct way to make a Fuel pump Cut-off ... (adrians_s13)

Re: (driftin8ez)

Re: (sochinkyeyesshut)

Re: The correct way to make a Fuel pump Cut-off ... (driftin8ez)

Re: (sochinkyeyesshut)

Re: (lenso)

Re: The correct way to make a Fuel pump Cut-off ... (IHeartTurbo)

Re: The correct way to make a Fuel pump Cut-off ... (driftin8ez)

Re: The correct way to make a Fuel pump Cut-off ... (vroom-chirp)

Re: The correct way to make a Fuel pump Cut-off ... (driftin8ez)

Re: The correct way to make a Fuel pump Cut-off ... (skylinekin)

Re: The correct way to make a Fuel pump Cut-off ... (Drewster)

Re: The correct way to make a Fuel pump Cut-off ... (skylinekin)

Re: The correct way to make a Fuel pump Cut-off ... (Seto)

Re: The correct way to make a Fuel pump Cut-off ... (skylinekin)

Re: The correct way to make a Fuel pump Cut-off ... (skylinekin)

Re: The correct way to make a Fuel pump Cut-off ... (SirSilvia)

Nissan Forums

Infiniti Forums

Datsun Forums

Technical Forums

Classifieds / Marketplace

Nissan Motorsports

General Forums