2G Cranks but doesn’t start (no power to starter signal wire)

[954g63gst]

I have a 97 gst manual. I relocated the battery to the trunk. I started the car so I knew that worked.

From there I dropped the fuel tank removed all the fuel components and replaced everything with the STM tank to rail kit, installed a FUELLAB FPR, and complete -6an line.

In the process I disconnected the engine harness and tucked most everything I could. I found the reverse sensor wires were cut so I connected and soldered them (see pic).

While removing the tank I noticed the rear o2 sensor was installed but the wires where cut so I replaced the sensor with a new narrowband one but since the car came with ECM Link V3 I ordered an innovate LC-2 digital air/fuel ratio sensor controller (not installed till I can start my car).

The car came with pro sport boost and a/f gauges boost wired and worked fine since day I bought the car. The Air/Fuel gauge never was wired up but the rear o2 wire next to ecu was cut and labeled rear o2. I pulled the ecu to verify ECM was installed and correctly.

I have all the interior pulled out so everything is accessible. Once I finished the fuel lines and f/p relay the car cranked but did not fire up! My DSMlink cable does not have a green light lite up so I can’t use link. I have multi meter and not afraid to pay for what’s needed

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[dustyboner]

it looks to me like the fuel pump is wired wrong.
so if the blue wire is 12v+ from the battery
the black is ground (-)
the white wire is 12v+ to the activation coil
yellow 12v+ to the fuel pump

you would want it wired like this:
with the white wire should attach to the (black/blue) that feed 12v+ from the fuel pump relay to the fuel pump (stock wiring) -- that way when the OG fuel pump relay triggers it activates your rewire relay
then you want one side of the fuel pump connector to go straight to ground

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[954g63gst]

Yes

it looks to me like the fuel pump is wired wrong.
so if the blue wire is 12v+ from the battery
the black is ground (-)
the white wire is 12v+ to the activation coil
yellow 12v+ to the fuel pump

you would want it wired like this:
with the white wire should attach to the (black/blue) that feed 12v+ from the fuel pump relay to the fuel pump (stock wiring) -- that way when the OG fuel pump relay triggers it activates your rewire relay
then you want one side of the fuel pump connector to go straight to ground

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ok so I just reconnected fuel pump ground back to the harness with an extension yellow wire Your saying ground it to chassis?
yes. white wire is connected to black/blue harness 12v and #86 on relay
black comes from #85 on relay to ground

 

[dustyboner]

here is a quick edit of the wiring diagram. hopefully it shows you what you need to know.

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[NOSLO2PT0]

Have someone crank the car while you watch fuel pressure gauge. If no Pressure, fuel pump no worky. Then chase down wiring

 

[954g63gst]

here is a quick edit of the wiring diagram. hopefully it shows you what you need to know.

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So looks like stm swamped the black and white wires Dusty black/blue from harness goes to what # on the relay?

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[NOSLO2PT0]

30 - feed wire from battery
87A - Not used
87 - when cutting stock 12V pump wire, this is to the pump
86 - when cutting stock 12V pump wire, this is to the car
85 - ground

This is how your relay should be hooked up.

Beat me to it. Just match up the wire color to the prong on the relay

 

[1990TSIAWDTALON]

Beat me to it too!!!
Those are the correct pinouts for the relay. If it is wired that way, it should fire the pump up.
If you "jumper" your Yellow and your Blue wires, the pump works, correct?

 

[954g63gst]

30 - feed wire from battery
87A - Not used
87 - when cutting stock 12V pump wire, this is to the pump
86 - when cutting stock 12V pump wire, this is to the car
85 - ground

This is how your relay should be hooked up.

This is how it is wired right now and what’s happening is Iam not getting the signal from the ecu to turn it on if I supply 12v to the black connector on the firewall my rewire rely turns the pump on meaning I am not getting signal from the ecu Because I don’t have power to the cps or ignition or CAS I unplugged the engine harness and re installed it after I removed a/c and battery and redid my fuel lines.

the ecu needs to see ignition and rpm to activate factory fuel pump relay but I don’t think my wires are right or I don’t have something plugged in Can you guys see the rely is wired how your explaining it just black and white are switched on the pigtail that’s how stm sent it but 12v from harness is wired to #86 and #85 is grounded to chassis
Fuel pump ground is wired to ground on factory harness Is that wrong? I feel like it’s all wired how you guys say it just black and white are put in the connector wrong I took the pic of the relay next to pigtail in the exact way it plugs in so you can see where each wire goes to which #

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[954g63gst]

Beat me to it too!!!
Those are the correct pinouts for the relay. If it is wired that way, it should fire the pump up.
If you "jumper" your Yellow and your Blue wires, the pump works, correct?

Yes I jumped the blue to yellow pump turned on Why won’t the ecu activate it Is what I need to chase

 

[1990TSIAWDTALON]

If the pump works with the test connector, then your pump ground is ok where it is.
No 12v+ from the original FP relay. Check the original relay. Is it clicking? Is it GETTING 12v+ and is it OUTPUTTING the 12v+.
That is what is needing ran down.

 

[954g63gst]

If the pump works with the test connector, then your pump ground is ok where it is.
No 12v+ from the original FP relay. Check the original relay. Is it clicking? Is it GETTING 12v+ and is it OUTPUTTING the 12v+.
That is what is needing ran down.

Great Now does anyone know how to chase power to CPS, Ignition,CAS to ecu to MPI to factory f/p relay to new relay??? If that is even the correct way

 

[dustyboner]

i usually just look at the diagram on the relay since some have internal diodes. some also have diodes on the plug.

30 is to the battery
87 is to one side of your fuel pump
86 is to the blue/black wire
85 is ground

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like this diagram shows that it has no internal diode meaning that polarity doesn't matter on the activation coil (85 and 86)

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[1990TSIAWDTALON]

Start at the original relay and check it for 12 volts ready and waiting for the relay to "relay" the power on down the wire.
One side of the relay should be HOT when the key is on and the other leg will be waiting for it to transfer the voltage out to the 2nd relay now.

 

[954g63gst]

Start at the original relay and check it for 12 volts ready and waiting for the relay to "relay" the power on down the wire.
One side of the relay should be HOT when the key is on and the other leg will be waiting for it to transfer the voltage out to the 2nd relay now.

Start at the original relay and check it for 12 volts ready and waiting for the relay to "relay" the power on down the wire.
One side of the relay should be HOT when the key is on and the other leg will be waiting for it to transfer the voltage out to the 2nd relay now.

What wires am I testing I don’t hear a click when I turn the key

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[1990TSIAWDTALON]

You got me on that, since I am at work and I only have 1g cars.
SOMEONE with a 2g.............HELP!!!!

 

[dustyboner]

IF you need more info on the MPI and fuel pump relays,
take a loook at this nicely done write up by steve

https://www.dsmtuners.com/threads/2g-basic-ecu-mpi-circuit-function.497188

it has helped millions of people

 

[1990TSIAWDTALON]

Thanks Dusty!! (and Steve)

 

[954g63gst]

IF you need more info on the MPI and fuel pump relays,
take a loook at this nicely done write up by steve

https://www.dsmtuners.com/threads/2g-basic-ecu-mpi-circuit-function.497188

it has helped millions of people

Thanks that’s exactly what I needed So Iam not getting 12v on pins # 3 and 4 red/black MFI side but I do have 12v on fuel pump relay black/white wires #’s 3 and 4 it looks like I have two A-32 connectors under my hood how do I know witch one is correct?

 

[dustyboner]

if your not getting power to 3 and 4 on the MPI relay, check fusible link #4

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check here for info on iidentifing 2g engine bay connectors

https://www.dsmtuners.com/threads/2g-turbo-ecu-pinout-w-wire-colors.281763/

 

[954g63gst]

if your not getting power to 3 and 4 on the MPI relay, check fusible link #4

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check here for info on iidentifing 2g engine bay connectors

https://www.dsmtuners.com/threads/2g-turbo-ecu-pinout-w-wire-colors.281763/

This is very helpful because I might have the wrong connection where a-32 goes. There was a similar plug that also fit. let me check and I’ll let you know. The fuse 4 is good so I think I just have the wrong plug, I’ll switch it and see how things play out.

 

[1990TSIAWDTALON]

1g's have a plug that is the same and people, including me, have accidentally plugged it in and then had "gremlins".
I hope that is all that the issue is and glad the 2g guys came to the rescue!!!

 

[954g63gst]

1g's have a plug that is the same and people, including me, have accidentally plugged it in and then had "gremlins".
I hope that is all that the issue is and glad the 2g guys came to the rescue!!!

Seriously!! I thank them and you a lot.

I think I had the other connector plugged in and my starter never turned. Then I switched to the one plugged in now and I got the starter to turn but the fuel pump never turned on. I am going to have to learn a lot about connectors and wire colors to generations to figure this out.

I wonder if anyone made a complete break down of connector code placement and wire colors. I would be interested in doing so if I can find a spare engine harness. But I believe their is two for second generation.

 

[954g63gst]

Ok, so the plug on the harness I thought was the A-32 was not though it cranked the motor when I turned the key.

It did not supply constant voltage to MFI/fuel pump relay on passenger side of the console.

Which with the right A-32 connector plugged in, I get power to both black/white wires on MFI and power to fuel pump relay red/black wires but the car won’t crank. Also the ISC buzzes for a second then stops when I turn the key all the way?

 

[dustyboner]

I am going to have to learn a lot about connectors and wire colors to generations to figure this out. I wonder if anyone made a complete brake down of connector code placement and wire colors. I would be interested in doing so if I can find a spare engine harness. But I believe their is two for second generation.

i fuct up,
this:

check here for info on iidentifing 2g engine bay connectors
https://www.dsmtuners.com/threads/2g-turbo-ecu-pinout-w-wire-colors.281763/

was supposed to be this link:

https://www.dsmtuners.com/threads/2g-dsm-engine-bay-electrical-connections.298047/

download THIS
for connector placement, it starts on page 54 (of the pdf)
and make sure and go over how to read circut diagrams on page 76 (of the pdf)

the color codes are on page 81(of pdf)
and they are also on the bottom of every 2nd page of the diagrams. if thst doesn't make sense now, it will after you start looking at the diagrams.