feul pump wont come on ?

[ma70suprawoner]

hey i just finished wiring my 1jz into my 89 supra and i know that the fuel pump was controled by the mass air flow sensor so how do you bypass the wiring for that? i should mention that this happens when i try to crank it over i jump started the pump just to see the motor run but im searching for a permenint salution and also do the stock injectors on a 1jz need a resitor pack ?

 

[mkiiichip]

Ground the green wire at the B1 plug. Its the signal for the circuit opening relay.
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=54

The tt 1jz does not require a resistor pack, not sure about the others.

 

[f00g00]

Check the fuel pump relay on the right fender. I had some aftermarket hood struts that would come off as I lowered the hood and it would extend into the relay and damaged the wires.

 

[87supraguy]

Ground the green wire at the B1 plug. Its the signal for the circuit opening relay.
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=54

The tt 1jz does not require a resistor pack, not sure about the others.

hey i just tried this and it didn't do a thing. i cut the green wire on the female side of the connector and tried to ground the wire going towards the connector and also coming out of th connecotr and no difference. any further insight?

 

[mkiiichip]

Do you still have the relay and resistor on the RF strut tower? Is it bypassed?

 

[87supraguy]

No those were removed. I was told with a jzz30 ecu they weren't needed. Apparently I need to do some more reading. To bypass them is that the 12 volt mod I've heard about? How do I bypass them exactly?

 

[87supraguy]

Do you still have the relay and resistor on the RF strut tower? Is it bypassed?

are the resistors and relays on the strut tower needed?

 

[mkiiichip]

No there not needed, but if they're taken out, they need to be bypassed.

This is for an 89, so you may want to make sure your wire colors match.
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=46

At the "fuel pump control relay" (the one you removed) you need to jump these two wires.

light blue with black
black with red

 

[87supraguy]

it didn't work... seems as if there is no power to those terminals or to any in that connector as a matter of fact,

i didn't check actual voltage but used a test light and noticed no power at any terminal at the relay connectors, resistor connector or FP connector.... this is why i looked at all the EFI related fuses. i'm gonna borrow a buddies relay and see what happens (but then again may not do much if theres no actual voltage or power running through the lines.)



this car was running before off this fuel pump like normal. i know the ecu help control the FP right? is there a wire the i can check ther for power? if this effing rain stops maybe i'll recheck all my grounds.

 

[87supraguy]

so i just tried to bypass the the relay by the pass side strut tower (wire colors were the same) it didn't work...:dunno:? i even tried to jumper the fuel at the diagnostics box jumping B+ to Fp and nothing. the EFI fuses are all fine.
pics of how i jumpered things. let me know if i did it wrong.

 

[mkiiichip]

Do you have power at the B+ pin?

Jumping FP and B+ bypasses the entire control system. So time to start looking elsewhere.

If you do have power at B+ (with the key on). next see if that sends power to the pump (remove the plate in the trunk). If you do have power, its a bad pump, if not, an open power wire (black with red).

 

[87supraguy]

Do you have power at the B+ pin?

Jumping FP and B+ bypasses the entire control system. So time to start looking elsewhere.

If you do have power at B+ (with the key on). next see if that sends power to the pump (remove the plate in the trunk). If you do have power, its a bad pump, if not, an open power wire (black with red).

interesting. i'll check today for power at the B+ terminal since the rain finally left this morning.

 

[87supraguy]

for some reason there was no power to the B+ just to test the fuel pump, i ran 12v straight to the Fp terminal and Yeah Beeeyotch!!! the fuel pump turned on... cranked it and for some reason it would not start!!!!! (Fuck here we go again!!!).

i became curious and pulled out my diode tester to test for spark and injector pulse ... i saw no injector pulse. i decided to unplug the AEM FIC and see if there was any change and plug in the jumper harness.

boom fired right up! this was the motivation i needed to see!!! not sure why it's not running with the FIC all of a sudden which sucks cause i just got it tuned right before buying this car.... that's something for another day.


i went shopping for supplies to do the 12v mod. i'll start doing this tonight.

 

[mkiiichip]

So, when you plug in your piggyback, you no longer have power at B+? IDK what the issue is, but you MUST have power there, to run.

 

[87supraguy]

actually to be clear, with the piggy back plugged in and me running stright 12v from batt to Fp terminal (fuel pump on) the car will not turn on. with fuel pump still on unplug piggyback and plug in jumper harness it will fire right up no issues..... this set up worked perfectly on my 87 all i did was transfer engine, harness etc everything. i didn't mess with the harness or anything. this 89 was working also prior to the swap. worried cause i've done a few mods (bigger injectors, bigger single turbo) and worried about emissions if i can't get it to run with the FIC. ( i just got it tuned and dialed in about 2 weeks before the swap.)

 

[wht95scort]

DR tweek made a new harness adapter to be installed inplace of the big green relay. I was having the same issue. I installed the item from him and the car starts like it should. It also doesnt let the fuel pump always run with key on.