Bad Fuel Pump Relay

After a considerable time of trouble-free motoring in my 1989 C900 T8S, she let me down today :( We went off for a pleasure drive around the Yorkshire
Dales and during an overtake, all power suddenly left the car ... Very much like when the fuel cut-off switch activates at high boost. Carrying on a little way up the road, I found that if I let off the accelerator the car would carry on, but as soon as I put down any power, simply nothing happened. It felt like the car was not even on!
Okay, so I pulled over and let it idle for a while and it seemed okay to carry on. About a mile later, going downhill, I heard a popping noise that was much louder than the normal overrun grumble. It sounded like a cylinder was missing on each rotation. I put the clutch down and the noise stopped ... Lifted the clutch and it started again. Just as I pulled out of gear, the battery light came on and the car stalled. Argh! We were in the middle of nowhere on narrow country lanes and had no real idea where we were to call out a recovery vehicle.
I tried turning the car over a couple of times ... Nothing! I opened the bonnet and checked that all the hoses were on and that everything looked okay. I checked under the car to make sure there were no conrods or whatever sticking out through the case. After I'd turned the air blue with my foul expletives, I got down to checking the battery with a multimeter I carry in the car. 12.5V ... Fine. Next, turn the key ... No fuel pump sound. Pull the fuel pump and try a jump/test wire. Now it makes a sound and I'm very glad indeed that I have a sandwich box of relays, fuses, wires and other gubbins under the back seat. Would you believe it? I had a fuel pump relay.
So ... Back on the road after only a few minutes of feeling pretty tense and worried. Sorry, but this is the most interesting thing that has happened to me and my SAAB recently. It's been a "rock" for a good couple of years now and no animals were harmed in today's mishap, although I did feel like taking something out on Olaf the stuffed toy moose who resides in the back of the car :)
On the good side, the car feels an amazing amount better than before. So much so, my wife noticed and commented from the passenger seat! What I thought was my exhaust manifold (the ubiquitous crack between cylinders 2&3) clicking has stopped and the high-pitched whine from the back of the car has also stopped. Must have been a very bad pump relay? I get higher sustained power than before - 0.8 bar through to over 5000 RPM in third and above, rather than 0.7-0.75 bar. This is on a standard T8! I wonder if the relay was kind of oscillating on and off, if that's possible?
To my final thoughts ...
1. Had I not had a previous C900, I would not have a spare fuel pump relay. Surely this is as good an excuse as any to continue on a long and happy succession of SAABs :) I gather the fuel pump relay is quite expensive and I'd like to have a spare (just in case, again) ... Anyone know a good outlet for less than a hundred quid? Failing that, what grade of wire would suffice for a longer term test/bridge wire. I had some thin stuff, which is okay for testing the 30/87 bridge, but I did not want to drive on it.
2. Why is it that when you break down on a remote country lane with nothing but the local wildlife chirping away, pop the bonnet, over a dozen Porsches of various ages decide to drive past you? How embarrassing! :) Must have been a "meet" out on manoeuvres for the afternoon.
Paul
1989 900 Turbo S http://saab.go.dyndns.org /
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relay.
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Most Bosch relays have a circuit board inside, the usual failure is cracking of the solder joints. I've never opened a Saab fuel pump relay but I've fixed many of the similar looking ones that Volvo uses. One thing to keep in mind is that a failing fuel pump often draws too much current (in excess of 10A or so) and will burn up a relay.
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There's nothing for giving you a smug feeling like having an unusual fault *and* happening to have just the bit to fix it :o) Reminds me of a breakdown I had 20 years or so ago in my mum's mini - the windscreen shattered, for no apparent reason, in the middle of nowhere, and at about 11PM. I was faced with the prospect of having to wait there until mobile phones became widespread! Years before that, she'd seen a polythene and wire "emergency windscreen" in Halfords' window and made it probably the only thing she ever bought in that shop. It then spent the intervening years knocking around in the boot as the only spare part she ever carried besides the wheel. All I had to do was peel away the soggy cardboard and I was on my way in minutes. Even the wipers still worked on it!
I have to say your symptoms sound a bit weird for a duff relay though. It could have gone a bit high resistance I suppose, but they normally just fail to pull in altogether or weld themselves permanently on. Mind-you, I suppose if it costs a hundred quid, it must be a lot more than just a relay?
Cheers,
Colin.
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