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1995 NG900 2.3L
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Discussion Starter · #22 ·
I am not going to test the fuel rail or check for fuel pressure at the engine. I've been troubleshooting the electrical side of the equation; fuses and relays.
I did this:

Another approach is connect a voltmeter or even a test lamp between fuse 32 and ground. Operate the starter, and while thestarter is turning the engine voltage should appear at fuse 32. If it does, the relay is working and the CPS is working.It shouldn't cost big bucks to replace the pump insert if you DIY
I used a test light on a good ground and on fuse #32 and it lit up.
I guess it's the fuel pump then as this, if correct, eliminates a faulty fuel pump relay and crank position sensor, but indicates the fuel pump gave up the ghost.
 

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Put jumper in fuel pump relay pins 30 & 87.
Now you hear pump running.
 

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Relay is switch, which connects power (battery voltage) to pump motor.
Relay pins are marked in relay itself. Pin 30 is switch common and 87 is switch normal open (closes when relay coil engages).

Pump motor is DC motor, which spins when voltage comes to positive pole and ground (car chassis) comes to another pole.

Jumper (jump wire) is (suitable) wire which connects (in this case) relay pins 30 & 87 together.
 

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WIS will not help if OP do not know what relay, jump wire or DC motor is.
 

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1995 NG900 2.3L
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Discussion Starter · #29 · (Edited)
@Harquebus : Do you have a copy of the WIS? That will also be of help.
No WIS. Does WIS help with identifying relay pins and doing simple diagnostic tests? I have the Haynes only, haha.

WIS will not help if OP do not know what relay, jump wire or DC motor is.
Thank you for the extra details. It takes a strong light and some magnification to see the pins 87 and 30 are labeled on the relay itself.
I think I need to manufacture my own jumper wire with pins (blades) soldered on the ends so the jumper wire will fit in the relay socket.

EDIT: do I need any particular gauge of wire to use for the jumper?


Many thanks
 

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No WIS. Does WIS help with identifying relay pins and doing simple diagnostic tests? I have the Haynes only, haha.



Thank you for the extra details. It takes a strong light and some magnification to see the pins 87 and 30 are labeled on the relay itself.
I think I need to manufacture my own jumper wire with pins (blades) soldered on the ends so the jumper wire will fit in the relay socket.

EDIT: do I need any particular gauge of wire to use for the jumper?


Many thanks
Download the WIS and install it. It will answer many of your questions. WIS and EPC for Windows - SaabCentral Forums

It's not as great for wiring in the NG900, but it will help if you spend some time getting used to it.

Meanwhile.. the Fuel Pump fuse is 15 amp. If you're jumping the hot lead to send power directly to the pump, that would suggest a 14 gauge wire.
 

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For such a short run, you can use a very small gauge wire. The worst it will do is get hot, in which case get a bigger wire. Generally speaking, a paperclip is sufficient.
 

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Generally speaking, a paperclip is sufficient.
I’d recommend something with insulation. I’ve attempted to use a paper clip to short the heater fan, and was surprised with a nice line of burned skin on my fingers. Once you see the smoke of the insulation burning, you know to yank your hands away
 

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Discussion Starter · #33 ·
For the sake of info, I found this little hack (and lots of other info on testing relays, etc). I just love the interwebz.

From a Porsche site: Jumping the Fuel Pump Relay JUMPING THE FUEL PUMP RELAY
It's exactly what @Mimmi suggested.

Insulated wire, crimped blade terminals... It's probably the exact same Bosch relay too.

I don't think these relays are all that fail-prone, but that jumper wire will "get you home". 🚗
 
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