Quick question about fuel pump rewire.

Looking at the diagram below:

First of all, in the front of the car where the fuel pump resistor and relay used to be - I see that the blue/red and blue wires are being pigtailed as E to F and A to B, would it be okay if they got switched and ended up E to B and F to A. I forgot to mark them before I cut the plug off and couldn't figure out which was which, still got them blue/red to blue but not sure if it's E to F and A to B or not.

Second and last question is regarding the stock wiring right to the pump itself, the diagram shows four wires being white/green, white/red, blue and black. My car, an S4 TI, has four wires but different colors; I have black/white, red, blue and black. So I used the blue and black but wanted to make sure this was correct.



I'm waiting for confirmation before finalizing the wiring so I appreciate any help here. Thanks in advance.

 

some how I did mine with only the left side of the diagram and yes blue and black are the improtant wires I'll see if I can find how I did mine

 

Ok, I'm pretty sure the wires at the pump are just slightly different due to the S4 vs S5 differences but I'm getting confused by some info in this writeup:

http://www.1300cc.com/howto/how2/rewire.htm
"yes the pump power is a black wire with a white strip, ground was straight black. the other 2 I had were red and blue, both were smaller and for the sending unit."

I was almost positive the blue wire was the power, so if anyone can clarify this I would appreciate it.

Also I still need to know about the pigtailed connections up front, does it have to be E to F and A to B or would it be okay if they ended up E to B and F to A.


Thanks.

I'm going to go jump the check connector and test the pump without starting the car just to see if it's getting power.

 

Another question of a bit different sorts, in the write ups around here I see people using huge wires like 10 ga for this stuff but it seems way overkill to me. Am I nuts or is 10 ga power for the fuel pump unnecessary?

 

I jumpered the check connector and turned the key to On and get distinct whining noise from the fuel tank so I guess it works huh. These Walbros are loud though geez.

 

I'm still hoping somebody could confirm that the pigtailed blue/red + blue connections are correct. The fuel pump turns on but I want to make sure I wired it correctly.

 

First of all, in the front of the car where the fuel pump resistor and relay used to be - I see that the blue/red and blue wires are being pigtailed as E to F and A to B, would it be okay if they got switched and ended up E to B and F to A. I forgot to mark them before I cut the plug off and couldn't figure out which was which, still got them blue/red to blue but not sure if it's E to F and A to B or not.

Second and last question is regarding the stock wiring right to the pump itself, the diagram shows four wires being white/green, white/red, blue and black. My car, an S4 TI, has four wires but different colors; I have black/white, red, blue and black. So I used the blue and black but wanted to make sure this was correct.

 

cut the damn resistor relay out. That's what I did. it's just one more thing to fail... Rx-7 owners are the only ones I know who try to keep them. On other cars people just bypass them. You're not gaining anything by relocating it, just a big clusterfuck and maybe a minisclue difference in fuel consumption at idle. A previous owner had relocated my resistor relay and the car was still leaning out. There could have been a gazillion things that were wrong with it, from the resistor relay itself to any of the solder joints.

splice those blue/blue-red wires together at the front like you already, and don't run anything to the back except one relay to trigger juice straight from the battery.



And be VERY CAREFUL of those pump wires. They change colors before and after the plug in the back of the car. The blue wire on the rear harness side does not connect to the blue wire on the fuel pump side of the connector iirc.

this is how you need to wire the extra relay (not a relocated resistor relay) after you splice those 4 wires together in the front:

87: wire directly from the battery, fused
30: wire from the relay to positive lead on the pump
86: blue wire from the original fuel pump harness. (it is black/white on the pump side of the connector though, at least on my 88 car). this triggers the relay.
85: chassis ground for the relay itself


See my old thread: https://www.rx7club.com/2nd-generation-specific-1986-1992-17/pics-my-overkill-fuel-pump-rewire-732904/ . In that thread I mention that it may not be the best idea for people on stock ECU or stock FPR to delete the resistor relay... bah, I doubt it makes a difference. There are plenty of people doing T2 swaps on n/a harnesses and putting in an upgraded fuel pump. They don't commonly any problems. I also ran 8 gauge wire in that thread directly in the tank. That's not necessary as all, I just kind of did it just to say I did it.

 

thats how i did mine

 

Ok, so I'll delete the resistor pack, when I do that what do I do with the black/white and green/red wires that I had run to the back? Should I connect them at the front or just cap each one separately?

And I'm going to go check the wires at the pump again right now.

Thanks for the help here.

 

cut and tape up the wires you ran to the back of the car from the stock resistor relay. You don't need them anymore. All you need are the wires in the crude diagram I posted.

 

Okay, I removed the resistor relay and rewired the new relay. The fuel pump power wire ended up being black/white, the blue wire is for the sender.

Thanks for the help.

 

for some reason my C is green/red and my D is black/white. Just wondering what should I do?

 

also, why does it have to be speaker wire? Why not just regular 12/10 gauge wires?

 

Should be a fuel safe wire like this.

http://www.etrailer.com/Accessories-...ka/10-1-1.html

 

Id hate to bump an old thread, but i was just wondering if anyone had a t2 with this rewired setup. Im getting my rtek in and addressing all my fuel issues before i start to do mods, so i wanted to know if taking out the entire resistor/relay pack will effect driveability and idle. This way seems alot more simpler as well as reducing alot of old wiring that comes with the car. ALSO i wanted to know, according to this diagram, the original ground wire going to the pump seems to me that it is just cut and left out from the new relay. Therefore having a new ground wire going from the relay to the body (Connector 85 on the relay). Is this true? ALSO! this post should honestly be on the Archive... Just saying!

 

The resistor pack helps gas mileage a bit on cruise and low rpm. It drops voltage to pump to 9v and on boost / high rpm to at least 12v. The key here is 12v. The wirings on these cars are old and corrosion drops voltage to important areas where it needs 12v, fuelpump being one.
I've noticed it drops to 10v on boost with headlights on and accessories on (I don't mean stupid boom boxes).
You'll be using new wires and no pack and that will give the pump at least 12v all the time.
I did this YEARS and YEARS ago and gas mileage didn't hurt that much.
Whenever I can, I cut out and use clean thick wires.

And...ALWAYS ALWAYS disconnect battery/ use a relay/ and fuse when doing any work involving 12v .