Need help!!! Walbro Pump and my shitty wiring! 2jzgte swap relies on this!!!!!

[SupraMario]

Ok, So As stated my crap wiring skills have put me in a rut. So I did the 12v relay and the 12v resistor mod. Well the problem is it is only getting power when I take and put 12v directly to my pump from the battery. The car then fired right up!

On the NA 1987
I have found FP and B+ and I wired(sodered) them together, well as far as I know B+ = Black with Red rings, and FP = Yellow.
Well Tonight my father and I found out the the blue wire is the 12volts, not the black and red rings, or the yellow.

So What is wrong? This 2jzgte swap relies heavily on this, PLEASE PLEASE HELP!!!

Also, is the walbro supposed to run all the time? Cause it is LOUD!

The goddamn robots john...

 

[IJ.]

OP feels this will get more/quicker responses in general so it's back again

 

[SupraMario]

Thanks Ian.
Yea no one checks the (other engines sub forum)

 

[Dr Tweak]

Uh.... you actually don't need to do that at all, with the way I wired it up, you connect the FC wire to a switch which goes to ground and when it's on, it's running 100%. The FP wire isn't connected to anything anymore!!!

Hope that helps!

-Doc

PS: Where were you told that you need to do this? Because that info is wrong, wrong wrong, and we should make sure it's fixed.

 

[SupraMario]

Uh.... you actually don't need to do that at all, with the way I wired it up, you connect the FC wire to a switch which goes to ground and when it's on, it's running 100%. The FP wire isn't connected to anything anymore!!!

Hope that helps!

-Doc

PS: Where were you told that you need to do this? Because that info is wrong, wrong wrong, and we should make sure it's fixed.

HAH! Wow!

I just got this from looking around, I figured I would have to by pass the resistor that makes the FP only get 12 volts.

Well that was simple! Awesome Doc, time to get out of bed and go see if it works now!

 

[jdub]

Tweak - Just to be sure I understand what you are saying, your advocating disconnecting the FC wire from the ECU and installing a switch to ground? Then the driver manually operates the switch (or leaves it on) to turn the pump on with the ignition on?

If this is correct, you realize you're bypassing a safety feature of the ECU...the pump will run as long as the ignition is on.

D34 - When you say "12V relay mod", are you wanting to install a relay in the back hooked up to battery power to run the pump?

 

[SupraMario]

Tweak - Just to be sure I understand what you are saying, your advocating disconnecting the FC wire from the ECU and installing a switch to ground? Then the driver manually operates the switch (or leaves it on) to turn the pump on with the ignition on?

If this is correct, you realize you're bypassing a safety feature of the ECU...the pump will run as long as the ignition is on.

D34 - When you say "12V relay mod", are you wanting to install a relay in the back hooked up to battery power to run the pump?

Yes this is something I was wondering, why does the pump always run, I hooked everything back up as the Doc said and it runs but the pump is on ALL the time.

Yes I did the 12 v relay, but it was not working properly because of the switch the Doc put in.

The other reason I should have read, and it should be known, is the 12v relay mod IS AND SHOULD ONLY be used for people with bad wiring in the back... IT IS NOT NEEDED if everything is good back there. I don't know why I did it.

The by pass of the fuel resistor mod is the only thing most people need to do when installing a walbro to get the 12v.

Correct me if I am wrong but after everything is said and done, the relay is worthless.

-Mario

 

[isnms]

I don't have the answer for you. I tried to get some discussion on this - Fuel pump upgrade & wiring - but has not gone anywhere.
I do have three different wiring options diagrammed. Maybe one could help you.

 

[jdub]

Not completely true...the 12V relay in the back essentially replaces the stock FP relay. Walbro pumps pull a bit more current...the stock wiring (assuming good condition) can handle it, but using 10GA battery power is is much better, especially if you have the battery in the back. Power to the pump travels a shorter distance.

Grounding FC (taking FC away from ECU control) is a bad idea. The ECU uses the CPS Ne signal to determine if the motor is running and grounds FC internally. If the motor suddenly stops (i.e. a wreck), fuel pump operation is terminated to alleviate a fire hazard. Power to the stock pump comes from the circuit opening relay...it has inputs from STA at the ECU to control the stock pump on engine start. You want to keep this relay.

In your case, you want to use the stock wiring to actuate the new 30A relay, using the power from the circuit opening relay...FC controls the circuit opening relay per above. Connecting B+ and FP is correct, but it has to be FP to the pump, not from the ECU (yellow wire).

In my '89 TEWD:
+B = Blue wire w/ black stripe
FP (to pump) = Black wire w/ red stripe...pretty sure this is your black w/ red rings wire...confirm by looking at the one going into the tank.

All you have to do is jump or connect these two wires on the harness side of the fuel pump relay connector...you can remove the relay and the resistor. You now have a ECU controlled wire to the rear to actuate your new 30A relay, for normal operation and engine start...call it FP if you like

The by pass of the fuel resistor mod is the only thing most people need to do when installing a walbro to get the 12v.

And that's pretty easy too...just jump the two wires on harness side connector to the resistor. Use at least a 12GA wire. The pump will always run at 12V

 

[SupraMario]

Yes but what about the wiring Doc did? The fuel pump switch. Black with red stripe and blue is the bypass of the resistor for 12 volts. BUT I still have that switch, If I just grounded it then it will still be on all the time. Should the pump run ALL the time? I thought that this was a possitive pressure system, meaning fuel pump runs for a bit on start up and goes until the engine is sucking in the gas basically from vacuum? Or am I wrong?

So the pump has to run ALL the time yes? or no?

 

[jdub]

Mario - Dump the switch and reconnect the FC wire to the ECU. Re-read the 2nd paragragh I posted above.
It will run all the time with the switch...it's dangerous if the car is in an accident.

Black w/ red stripe connected to Blue wire w/ black stripe also bypasses the stock starter relay, taking it and the resistor out of operation. If you wire it like I suggested, you will have all the features of the stock system, including fuel pump operation for start-up. the STA signal from the ECU enables this via the circuit opening relay. Once the engine is producing an Ne signal, FC keeps the circuit opening relay closed.

Just use the black/red wire to operate the relay you have in the back. Is your battery back there?

 

[SupraMario]

Mario - Dump the switch and reconnect the FC wire to the ECU. Re-read the 2nd paragragh I posted above.
It will run all the time with the switch...it's dangerous if the car is in an accident.

If you wire it like I suggested, you will have all the features of the stock system, including fuel pump operation for start-up. the STA signal from the ECU enables this via the circuit opening relay. Once the engine is producing an Ne signal, FC keeps the circuit opening relay closed.

Just use the black/red wire to operate the relay you have in the back. Is your battery back there?

No battery is not in the back. I realize that is dangerous, but I need to know if it can be run this way until I get to cookeville, it just needs to make one trip, and then I can rewire it, as I got pissed about the relay shit and cut it out, because it was causing problems.

I also did not do the wiring on this engine, so I have no clue how to wire this back into the ECU.

 

[jdub]

It wasn't the 30A relay causing the problem

Who wired the switch in to ground FC (green wire in my TEWD)?

Yes, it will work. I hope nothing happens...your last move before you go unconscious in an accident better be to turn off the ignition.

 

[SupraMario]

It wasn't the 30A relay causing the problem

Who wired the switch in to ground FC (green wire in my TEWD)?

Yes, it will work. I hope nothing happens...your last move before you go unconscious in an accident better be to turn off the ignition.

Always have always will. The wire for the FC was just bare from the harness, Doc did that, and I put the switch on.
It only needs to make 1 trip, then I will be fixing it.

 

[Jaguar_5]

In my '89 TEWD:
+B = Blue wire w/ black stripe
FP (to pump) = Black wire w/ red stripe...pretty sure this is your black w/ red rings wire...confirm by looking at the one going into the tank.

All you have to do is jump or connect these two wires on the harness side of the fuel pump relay connector...you can remove the relay and the resistor. You now have a ECU controlled wire to the rear to actuate your new 30A relay, for normal operation and engine start...call it FP if you like



And that's pretty easy too...just jump the two wires on harness side connector to the resistor. Use at least a 12GA wire. The pump will always run at 12V

This is the part that somewhat confuses me, If you're running a new relay, and a dedicated B+ line, the pump is getting the full voltage no matter what, so jumpering the +B and FP only ensures that the voltage stays at 12 volts to keep the relay engaged, correct?

Btw, Mario, have you checked the 12 volt mod with pics thread that we have in the technical section? Wiring up a relay is SO easy as long as you understand the basic principle

 

[jdub]

Jag - You can look at this 3 ways depending if you're using the stock wiring to power the pump, simple resistor bypass, or using the stock wiring to trigger a relay providing battery power to the pump.

1) Stock wiring to power the pump:
Connect +B = Blue wire w/ black stripe to FP (to pump) = Black wire w/ red stripe
The circuit closing relay is now powering the pump directly...it deletes the stock FP relay and resistor. The pump will run at 12V at all times.

2) Simple resistor bypass:
Jump the resistor connector on the harness side. The stock fuel pump relay is still active and switched by FP from the ECU (yellow wire). However, both positions on the stock relay are powered by 12V. The pump will run at 12V at all times...you will get a voltage "blip" at switch (as you do stock).

3) Stock wiring to trigger a relay providing battery power to the pump:
This is what you are talking about and is done to provide the 12V necessary (since the Bosch relay uses a 12V trigger). In this case, the circuit opening relay provides the power just like #1 above, but it is to the trigger side of the new relay. Power is provided to the pump via a battery hot wire on the switched side of the relay. Bottom line, you are correct

 

[Jaguar_5]

Wow, such a detailed response, what a fantastic wealth of knowledge you are, I love reading your posts

Thanks for clarification!

 

[SupraMario]

This is the part that somewhat confuses me, If you're running a new relay, and a dedicated B+ line, the pump is getting the full voltage no matter what, so jumpering the +B and FP only ensures that the voltage stays at 12 volts to keep the relay engaged, correct?

Btw, Mario, have you checked the 12 volt mod with pics thread that we have in the technical section? Wiring up a relay is SO easy as long as you understand the basic principle

LOL, yea I did, thats how I wired mine up, I talked with shaeff alot too about it. The thing I did not know is Doc did the bypass thing for me.

 

[jdub]

D34 - I was meaning to ask...how is pump wired now?

Is this on a 7M or 2J ECU?

The switch Doc installed...where is it? Or, is FC just grounded somewhere?

There might be a reason Doc wired FC the way he did, but I can't picture it.

 

[SupraMario]

D34 - I was meaning to ask...how is pump wired now?

Is this on a 7M or 2J ECU?

The switch Doc installed...where is it? Or, is FC just grounded somewhere?

There might be a reason Doc wired FC the way he did, but I can't picture it.

LOL nooo, 2jzgte ECU. The wire with the switch is right off the ECU, like its on the harness, but it has enough length to connect to the ECU itself, this wire is on a switch that is grounded back around to my engine bay. My pump is wired just like the Walbro is supposed to be wired. Basically when I turn on the ignition, pump is on, when key is in ON position.