So I still don't know why the alternator passed its bench test, but I picked up a second hand voltage regulator from a very nice chap online and swapped it in and all is well. The brushes on my old one were spent, so I suspcect that was the issue. I felt a little funny about getting a used one, but for $12 instead of ~$115 I figured it was worth a shot... not that I could even get one around here (didn't try the dealer... got too scared). Thanks for all for your input.
Matt
Thanks for the conclusion Matt.
Glad it worked - it usually does. Keep the old one and next time you're near a starter/alternator place buy a set or brushes - they're $2 and all BOSCH regulators use the same one; rebuild your own one and now you have a spare.
They didn't do it properly. ;-) Did you actually see the test bench - it's quite involved and expensive. Most smaller places wouldn't actually have one.
Last one I bought was approx 30 gbp so say $55.
It was in one of the national chains... and yes it looked quite expensive. they looked up the part and entered the number and then used specific connectors to hook it up... so i don't know why the conclusions were as they were.
Matt
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