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Saab: 1988 900s wont start, fuel pump relay, jumper wire


Question
QUESTION: Hi Jerry,

I was warming my car and went back to find it had shut off. When trying to restart It would catch for just a second and stop. I replaced the fuel pump relay, and removed the fuel pmp assembly, the main pump started when I put power to it and I replaced the smaller pre-pump. It still would not start. I looked back at some of your previous posts and connected a short wire from the # 27 fuse to the #30 fuse and the car ran as long as I had the wire connected, I could also hear the pump running as soon as the wire was connected. Where should I go from here? Any help will be greatly appreciated.

Thank you,
Greg

ANSWER: Greg:
 Based on your description, the problem is in the wiring between the fuel pump relay and fuse No. 30.  This can be checked by running a long wire from the outboard side of fuse 30 to pin 87B of the fuel pump relay. If the engine starts, then the problem is solved and you can permanently leave that wire in place, as all functions will be normal. If not, then you may get back to me and I will scan in and forward the schematic diagram which would allow you to reconstruct the entire relay drive circuit by obtaining access to pin 20 of the LH control unit located next to the fuel pump relay.  Sounds cryptic, but will be apparent when you see the schematic.
 Hope this helps,
         Jerry

---------- FOLLOW-UP ----------

QUESTION: Jerry,

I haven't had a chance to get back to working on the car until yesterday, and this may seem like a silly question but how do I run the wire to the pin on the relay with the relay in? Or to the wire on the bottom of the relay? Please let me know.

Thanks again for your help.

Thank you,
Greg

Answer
Greg:
  You may either solder the jumper wire onto the relevant pin, or perhaps more simply, obtain some automobile wire splices (Walmart auto department), AutoZone, etc,  which are blue plastic items that permit splicing one wire onto another. They are easy to use. Hope this helps,
   Jerry