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Saab: Fuel pump, crankshaft position sensor, fuel pump relay


Question
Hi Jerry,

Thanks for all the past help you gave to my wife Becky.  We changed the fuel pump, then replaced the relay. (had to take the lower dash out to get to the relay) I found it strange that both the pump and the relay died at the same time... until I noticed that with the new relay in the fuel pump now runs 24/7, even with no key in the ignition. I'm thinking this may have killed the last pump and relay... any ideas where we should look for the problem now?  We spent 3 hrs today on the various forums and have not seen this problem discussed.  Thanks, Jim & Becky.

Answer
Jim:
 I can only comment on the 1993 or earliuer 900's...from what we've seen, your vehicle may be different. Here goes:
 The crankshaft position sensor generates pulses as it rotates which energizes the spark circuitry (ignition amplifier is  located on left inner fender well on the older SAABS)and in turn sends the pulsed signal to the main engine controller. As long as these pulses are present, the controller energizes the fuel pump relay, keeping it on. So, it appears that in your case, the fuel pump relay is being kept on. The only way this could be so is (a) there is a short to ground somewhere  or (b) The main engine controller is faulty. If you wish, I can scan in the schematic and send it to you, or if you live close to Ledyard, you can stop over. There is no assurance that my info is fully applicable to your vehicle however.
 Hope this helps,
         Jerry