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By Tj 27
I have a 2009 957 3.6l v6 Cayenne. The battery was dead a few days ago so I replaced it. It now starts up just as it should but when run a diagnostic it says the alternator voltage is high reading 14.72. I’m assuming I need to replace the alternator to remedy this. I can’t find any information about replacing the alternator. Has anyone attempted this? It looks like it might be straightforward but my concern is whether or not the intake manifold has to be removed in order to get clear access. If anyone has any insight on this I would greatly appreciate it.
A voltage problem that has been plaguing my 2002 996 C2 , 911, for ages, is when I first start the car, according to a cigarette lighter type electrical gauge device, everything is ok showing 'about' 13.3 to 13.8 volts, and a green light on the gauge. It remains that way ( 13.3 to 13.8 volts) for about 5 miles or about 10 minute or so, being driven or just idling.
Then after that (a few miles or 10 mins) it starts dropping to as low as 12.8 to 12.2 volts,and in the red ? This always happens after the motor etc heats up,hence it appears to be a heat issue I think ? Last year I removed the alternator took it to a local alternator specialist that replaced the voltage regulator with an updated version ? And when bench tested it appeared fine.
However once back on the car, it happened all over again ? Brand new battery, all connections appear ok, it's only AFTER the car gets up to a normal operating temperature, after about 10 mins or so. It baffles the hell out of me, and I always carry my jump start box , just in case. Any ideas as to what it is ? I was thinking of just buying another alternator and taking a chance on thats what it is ?
Speaking of that, Pep Boys, Auto zone , O'Reilly's etc, sell them for about $155.00 with a lifetime guarantee ! The dealer wants an outrageous price, silly money, and a foreign car part place wants about $375.00 for a re-built Bosch. Any thoughts on the cheaper ones , and what my problem/issue could be ? This is a great car save for this alternator, electrical issue ??? Thanks a lot Dave.
Just finished installing a new alternator to starter cable and the thought I'd share a couple of pics of the old cable, a hint on replacing the ac compressor and the results of the install.First a couple pics of the old cable.Note where the rubber insulator melted to the attachment lug to the starter. You can also see some melting of the plastic cable wrap at the lug and a little further down.Little better pic of the melted point on the cable wrap. Might just be from engine heat but this cable doesn't come in contact with exhaust headers at any point in it's routing.This is a pic of the new and old cable starter attachment lugs side by side. New cable appears a bit thicker than the old and, as you can see, the primary attachment lug for the starter is a good deal more robust than the old one.As for the procedure, my thanks to equinox's DIY on the subject on 6speedonline.com, without which I would not have been able to attempt nor complete the swap. One helpful hint I might offer to his writeup is shown in the pic below.To simplify the re-install of the ac compressor I attached zip tie to the rear most bolt to keep it up and out of the way during the re-install. once I had the compressor back in place and had re-installed to two bolts in the front of the compressor, I cut the tie, holding on to it make sure it didn't wind up in nether regions of th engine bay, and the bolt fell right into place. Overall the install is challenging but not impossible if you have a fully stocked tool chest and some free time on your hands. The OOP savings over what a dealer would charge you will almost buy you a new set of Michellin Super Sport tires.As for the outcome, the difference is nothing less than amazing on my car. Can actually start the car with radio and AC on immediately after shutting down a fully warmed engine in the dead of summer and the car had not been on the trickle charger for at least 5 days. I started the process of removing the old cable a few days before the new one arrived and finished the day after. And while this wouldn't be a big deal on any other make of car on the planet, it is on this model 997 and well worth doing if you experience slow starts when your engine is hot.