Justin;1078287 said:
I tried two different setups, look at the pic below to see what I mean by Wire 1 and Wire 4:
Setup 1:
Power: 87
Wire 1: 30
Wire 4: 85
Ground: 86
Setup 2:
Power: 85
Wire 1: 86
Wire 4: 30
Ground: 87
Quick Q about "necessity" of 12V Fuel Pump Mod!?
- Thread starter rcsupra
- Start date
I tried two different setups, look at the pic below to see what I mean by Wire 1 and Wire 4:
Setup 1:
Power: 87
Wire 1: 30
Wire 4: 85
Ground: 86
Setup 2:
Power: 85
Wire 1: 86
Wire 4: 30
Ground: 87
This might help: http://tinyurl.com/5hjxm
Power from the battery should go to 30
The pump (wire 1) should go to 87
The original pump feed (wire 4) should go to 85
A ground should go to 86
Wires on 85 and 86 can be swapped, as can those on 30 and 87, but normal practice is to wire power to the movable contact and load to the fixed one. Just do it like I said...
Power from the battery should go to 30
The pump (wire 1) should go to 87
The original pump feed (wire 4) should go to 85
A ground should go to 86
Wires on 85 and 86 can be swapped, as can those on 30 and 87, but normal practice is to wire power to the movable contact and load to the fixed one. Just do it like I said...
And you can test that the pump is working through the diagnostic block. I believe you jumper B+and Fp. Someone (JJ) correct me if I'm wrong on those. I'm not where I have that saved right now.
Last edited:
ForcedTorque;1078364 said:
You're correct.
When you jumper those two, since the resistor is bypassed, 12 volts will go to the new relay you just installed, triggering it. Once the new relay is triggered the fuel pump will initilize.
Finally! The car is running:icon_bigg
Thanks JetJock for those settings. We found two blown fuses under the hood, one being the stock 15A FI fuse, and the inline 12V 30A fuse was blown as well. Perhaps this happened when we were trying different wiring settings. Not having a spare 15A on me, I put in an extra 30A in and replaced the inline fuse with another 30A and it fired right up.
The idle seemed a bit lower at first, but I think its gotten relatively back to normal after some driving. Just so I'm sure, I should not go into high rpm's/full throttle on the stock FPR correct? I've read Walbro/stock FPR can make you lean out, but I've read it can affect your idle so I'm trying to figure out if its one or the other or both.
Thanks JetJock for those settings. We found two blown fuses under the hood, one being the stock 15A FI fuse, and the inline 12V 30A fuse was blown as well. Perhaps this happened when we were trying different wiring settings. Not having a spare 15A on me, I put in an extra 30A in and replaced the inline fuse with another 30A and it fired right up.
The idle seemed a bit lower at first, but I think its gotten relatively back to normal after some driving. Just so I'm sure, I should not go into high rpm's/full throttle on the stock FPR correct? I've read Walbro/stock FPR can make you lean out, but I've read it can affect your idle so I'm trying to figure out if its one or the other or both.
You be welcome. Yeah, a little circuit analysis shows what you did would've blown fuses. Good thing you put one up at the battery like you should have or you would've smoked that wire.
I see you used the other way of circumventing fuel pump control. It's one of three methods you could have chosen from. That way is actually best because it completely removes the relay from the circuit.
I see you used the other way of circumventing fuel pump control. It's one of three methods you could have chosen from. That way is actually best because it completely removes the relay from the circuit.
Is there a downside to Jdub's easy method to get 12 Volts to the pump? It looks so much easier than running a wire from the battery, wiring a relay, and cutting into the stock wiring at the tank.
I don't know what the aftermarket pump draws but if it's anywhere near the stock one running a wire from the battery is a waste of time. Then again I also feel running the pump on 12 volts full time is, for the most part, one of the dumber mods out there.
Jdub's method of jumping the resistor is "bad" only in the sense it leaves the relay in the circuit. I've seen a few relays go tits up. Also, a relay contact that doesn't periodically operate is trouble waiting to happen.
Jdub's method of jumping the resistor is "bad" only in the sense it leaves the relay in the circuit. I've seen a few relays go tits up. Also, a relay contact that doesn't periodically operate is trouble waiting to happen.
Yep...the jumper I use just removes the resistor and provides a constant 12V through the stock circuit. It will not remain this way...a rewire with a new relay is in the plan 
The black thingy is a bypass capacitor and its purpose is to shunt ac noise from the motor to ground thereby preventing it getting back into the car electrical system. That extra wire goes to the +ve terminal of the pump.
rcsupra;1078450 said:
I experianced quite the opposit, with the stock FPR and a walbro my car ran very rich. The stock FPR is matched to the flow of the stock pump, if you look at a graph of stock v walbro the walbro flows alot more fuel.
ILikeCarsYesIDo;1073330 said:
Call me crazy, but I think we will see that the 9-12 volts is accounted for in TCCS, when 3p and brutus finish their work.
If you need to do this mod, you need to do all of it.
teedoff00;1066423 said:
It doesn't make the pump last longer, it is for tuning alone. More wattage to the pump doesn't make it last longer.
So you telling me all I got to do is jump this here and I am at 12v mod???
(here is the pic)
http://www.putfile.com/pic/8218052
So the way it sounds now, this mod isn't even needed unless you tune your car, so what would happed if you just jump the two wires like "j"dub" did while your tunning and go back to nine volts while driving normaly, or did I miss the point? I know stock runs at nine then goes to 12 volts. Walbro says it needs 12 volts to opereate, does he mean 12 to run efficeintly? or does he mean 9 volts is O.K. but 12 would be best.
I think the answer will be found if we just ask this question
John (Jdub), why are you going to reverse on your decision to get 12 volts by jumping the fuel pressure relay? You stated you will go with shaeff's method, which BTW, includes jumping that relay.
John (Jdub), why are you going to reverse on your decision to get 12 volts by jumping the fuel pressure relay? You stated you will go with shaeff's method, which BTW, includes jumping that relay.
So you telling me all I got to do is jump this here and I am at 12v mod???
(here is the pic)
http://www.putfile.com/pic/8218052