Rob O'Meara

I'm having trouble with my tt. On Saturday afternoon, as I was driving along with my fiancé, suddenly all the warning lights lit up and started pulsing. Immediately I pulled into a service station, cut the power and tried to restart. All I got was the telltale clicking noise as the dead battery tried to turn the starter motor. I called out the AA but found that, even when the car was jumped the battery was not being charged. We checked the alternator, but it appeared to be operating correctly. It got new belts last year. Apart from a hosed alternator assembly has anyone got any ideas? Is there an easy way to diagnose a faulty alternator? I have basic diagnostic probes.

Six months ago my car had its wiring loom replaced as part of the Porsche recall program. Could this have anything to do with the problem? If so I will get onto the OPC to rectify matters.

Cheers,
Rob

viperbob

Rob

I had a similar problem when I first bought my car. Idiot lights would even cycle even when driving. It was just a bad battery. Nothing else.

Rob O'Meara

OK thanks for the feedback Bob, but the AA technician put in a new battery and pointed out that it was not charging properly either. Is there a quick diagnostic test to see if the alternator is malfunctioning?

Q

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by Rob O'Meara:
<strong>, suddenly all the warning lights lit up and started pulsing. </strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Rob, I had the IDENTICAL thing happen to me.
It drove for the rest of the day, and then died altogether.

It was the Alternator.
Seek a second medical opinion <img border="0" title="" alt="[Wink]" src="wink.gif" />

krish

Rob,

Does your charging light come on with all the other lights with ignition on but engine not running? If it doesn't this could indicate either worn brushes or a blown regulator. Next question, if it does come on, does it go off once the engine is running?I'm assuming it doesn't else you would have mentioned it. If it stays on then it's either a blown reg or rectifier.

Simple test. Hook up a DC multimeter (digital would be ideal)to your battery terminals. Healthy charging circuit wth engine at idle but no load (a/c, lights etc all off) should read approx 13 volts dc. Anything less and you've got a problem.

I had a similar problem in my 964 and it was worn brushes. Unfortunately it comes as an assembly with the regulator. The bosch replacement part only cost me USD$20.00 I think.

cheers,
Kris
'97 993 tt
'89 535I
'89 Nissan 300ZXtt
'00 Trackmagic 125 cc shifter kart

Rob O'Meara

Thanks for the feedback guys. I'll take a look this evening and get back to you. I have an analogue multimeter which should do the trick. Nice to know Porsche alternators are composed of modular parts, though I'm expecting there to be a turbo-specific requirement to buy the whole assembly

Corte Loco

I had the same problem on my "94 964. Check your alternator at 2500 rpm with high beam lights, air cond at max, if you see anything bellow 13 or above 14, there´s the problem. I solved my problem with a rebuild alternator for arround US.200.

Rob O'Meara

Just a quick update to this situation. My local Porsche centre looked at the alternator and have pronounced it "dead". They suggest I replace the offending unit at a cost of around £1000 including labour. Assuming this is a complete rip-off (which most Porsche service amounts to) what would my trusty Rennlist colleagues do? I am loth to spend any more on this car, which in my opinion is an unreliable heap of crap.

Rob

Jeff 993TT

Rob, you should not go to the dealer then. Either replace it yourself, or go buy the alternator and pay some wrench to do it.

In fact, viperbob and I are going to help "yellow" to replace his alternator this weekend. You can get them pretty cheaply over here in the states from the standard auto supply houses ( napa, grand auto, etc ). I think they were around $350??.

Have you checked prices in over where you live?

viperbob

Well Rob, Jeff and I are scheduled to install a new alternator on another Rennlist members 993 C4S car on Saturday. Same issue as you. Dealer wanted $1,000 to do the installation. Be bought the part for $180 (I think thats right) and it will take us a few hours of work, drinking and general Porsche talk to get it installed. I would offer to help, but that is a long way to send the car just for an alternator. The job itself is not that hard if you are handy with a spanner, or have some friends that could help.

Good luck...



I'm getting worried Jeff. We are starting to post at the exact same time. And with the same information...

ca993twin

Viperbob,

A true Rennlister would offer to fly to "Jolly olde" to help Rob out through his obviously bad experiences. But "spanner"! Bob, you continue to impress.

Ian J

Rob,

Just had the alternator fail on my 1994 NA C2 whilst driving from Istanbul to London. Same systems......one by one the idiot lights came up, then lost all power before cruising to a halt in the middle of nowhere at 0230hrs.

Funny enough I have also just had the loom replaced býut I think this is coincidence and the failure reflects the age of the vehicle (9 yrs), its high km (183,000) and the fact that it only gets occassional use rather tahn the loom replacvement.....

In the end I abandoned my car and it was recovered to the OPC at Reims.


Charge for replacing with a new alternator came to just over 1,000 Euro's so GBP 1,000 sounds steep to me ( having said that I have noticed that as with the US things are srating to be priced at the same number Euros on the Continent as they are GBP in the UK...welcome to rip-off Britain !).

Good luck
Ian
1994 C2 Istanbul

Rob O'Meara

Thanks a lot guys, you're making me feel guilty for taking the car to Porsche! I'm not the best at auto mechanics - I don't trust myself to put the bits back together in the right order. But it's about time I picked up a spanner and tackled the task myself. I'll take a look at pcar.com to see if there's a DIY. I did consider doing it myself before but couldn't work out how to remove the intercooler. Is this documented anywhere?

Is there a standard part number for the alternator?

Thanks again.
Rob