Alternator Issues?
Thread Starter
Track Day
Joined: Apr 2009
Posts: 24
Likes: 0
From: 35244
Alternator Issues?
OK, brand new to these unique air-cooled beauties, so here goes
None of the gauges function on start up. When I rev the engine the gauges come to life but the alternator warning light comes on and stays on. First thing I did was check my belt ... it was OK. The Alternator was rebuilt only 2,500 miles ago. Strange thing is I can drive it for hours and when I come back and hook it to my battery tender it indicates I am at an 80% charge and gets back up to 100% very quickly. So if my alternator is not charging the battery, I guess the initial charge lasts much longer than I thought it would (1988 Carrera).
Next step is to pull the alternator and have it tested unless someone has a better idea.
None of the gauges function on start up. When I rev the engine the gauges come to life but the alternator warning light comes on and stays on. First thing I did was check my belt ... it was OK. The Alternator was rebuilt only 2,500 miles ago. Strange thing is I can drive it for hours and when I come back and hook it to my battery tender it indicates I am at an 80% charge and gets back up to 100% very quickly. So if my alternator is not charging the battery, I guess the initial charge lasts much longer than I thought it would (1988 Carrera).
Next step is to pull the alternator and have it tested unless someone has a better idea.
Team Owner
Joined: Aug 2005
Posts: 28,425
Likes: 1,621
From: Cambridge Ontario Canada
well put a voltmeter on it while idling and see what you get first if it is below 13 volts ( actually there are very specific value at idle and higher RPM ) then I would say your alternator/ regulator is toast .
BTW you may still be charging the battery , just at a rate below the threshold for the diode. report back what your DVM shows at idale and about 2000 RPM . We will be able to help you better then ..
BTW you may still be charging the battery , just at a rate below the threshold for the diode. report back what your DVM shows at idale and about 2000 RPM . We will be able to help you better then ..
I haddah Google dat
Rennlist Member
Rennlist Member
Joined: Nov 2008
Posts: 11,501
Likes: 5
From: Fresno, CA
You should check the electrolyte level in the battery, and clean your battery clamps. The 3.2 Carrera is known to eventually corrode the positive battery clamp, which has to be cut off and replaced. I would also buy a heavier, and longer ground cable at the same time. If your battery is not holding charge, then it has to be replaced.
Team Owner
Joined: Aug 2005
Posts: 28,425
Likes: 1,621
From: Cambridge Ontario Canada
I think what he is saying is that the barttery will hold charge, but it is not being replenished by the alternator , which makes sense since the light it is on. But for the 100.00 I would certainly throw one in if is does not test well.
Last edited by theiceman; Apr 6, 2009 at 11:02 AM.
Thread Starter
Track Day
Joined: Apr 2009
Posts: 24
Likes: 0
From: 35244
The light stays on with the key off. I just ordered a voltage meter that allows me to test both the battery charge (ignition off) and the alternator (car turned on). I will let you know what it tells me once it gets here.
This is the type that plugs into your lighter socket and gives a digital readout of the charge.
I suspect the alternator is not charging at the right level, but still charging to some extent, since the battery seems to be staying pretty well charged. Perhaps it is just a gremlin that is making the light go on for no reason, but in my experience (limited as it is), generally there is a reason.
I look forward to learning all I can about my new car. Just ordered a Carrera 3.2 technical book. Any other reading recommendations for my education would also be appreciated.
This is the type that plugs into your lighter socket and gives a digital readout of the charge.
I suspect the alternator is not charging at the right level, but still charging to some extent, since the battery seems to be staying pretty well charged. Perhaps it is just a gremlin that is making the light go on for no reason, but in my experience (limited as it is), generally there is a reason.
I look forward to learning all I can about my new car. Just ordered a Carrera 3.2 technical book. Any other reading recommendations for my education would also be appreciated.
I haddah Google dat
Rennlist Member
Rennlist Member
Joined: Nov 2008
Posts: 11,501
Likes: 5
From: Fresno, CA
If you alternator light stays on with the key off, then your diodes are shot, and you need to get a new alternator.
I would forget about having it rebuilt because Bosch offers an excellent rebuild program. I think a rebuilt Bosch, with warranty, and with a brand new voltage regulator, should cost around $160 if you bring your old alternator with you.
I would forget about having it rebuilt because Bosch offers an excellent rebuild program. I think a rebuilt Bosch, with warranty, and with a brand new voltage regulator, should cost around $160 if you bring your old alternator with you.
Trending Topics
Advanced
Joined: Mar 2007
Posts: 89
Likes: 0
From: Toronto
If you alternator light stays on with the key off, then your diodes are shot, and you need to get a new alternator.
I would forget about having it rebuilt because Bosch offers an excellent rebuild program. I think a rebuilt Bosch, with warranty, and with a brand new voltage regulator, should cost around $160 if you bring your old alternator with you.
I would forget about having it rebuilt because Bosch offers an excellent rebuild program. I think a rebuilt Bosch, with warranty, and with a brand new voltage regulator, should cost around $160 if you bring your old alternator with you.
Rennlist Stories
The Best Porsche Posts for Porsche Enthusiasts
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look
Verdad Gallardo
10 Porsche Colors That Have More Personality Than Most People
Verdad Gallardo
Guntherwerks' Final Speedster Creation Is the Ultimate Porsche Restomod
Verdad Gallardo
10 Reasons I Hate Going to the Porsche Dealership (& the 1 Reason I Stay)
Joe Kucinski
Porsche Shakes Up The Nürburgring Lap Record Table Once Again
Verdad Gallardo
6 Ways the Porsche 911 GT3 S/C Redefines Performance
Joe Kucinski
10 Wildest Homologation Specials Porsche Ever Sold
Verdad Gallardo
Super Rare RUF BTR III Comes Out of Hibernation, Looking For a New Home
Verdad Gallardo
10 Porsche Opinions That Can Start a Fight
Joe Kucinski
I haddah Google dat
Rennlist Member
Rennlist Member
Joined: Nov 2008
Posts: 11,501
Likes: 5
From: Fresno, CA
Edit: ok, I see what you're saying. $250 is still a good value. Maybe I got the last one off the shelf at World Parts? I have had good luck buying rebuilt Bosch starters and alternators over the years. I'd just call around. Try the vendors in Excellence magazine, or see if you have a World Parts near you. I got mine at Sebring West here locally. I just drove on down there and brought my old one with me. I even pulled my old voltage regulator, not that I'd ever plan on using it.
Thread Starter
Track Day
Joined: Apr 2009
Posts: 24
Likes: 0
From: 35244
OK ... I finally obtained a voltage regulator (digital that plugs into the cigarette lighter.
Before starting the car, but after turning on the ignition, it reads 12.4. The manual indicates this is the charge in my battery. After warming up the car to operating temp and about 2,000 rpms it reads 14.x.
The alternator light comes on only when the car is running. I keep the car on a battery tender so that would explain the adequate battery charge. The alternator was just rebuilt 3,000 miles ago. Could it be bad diodes or something else that might have been missed with an alternator rebuild?
BY the way someone keyed my new to me 1988 Carrera in two places the other day. Boy am I pissed. I wish I had caught them in the act. I guess the new is now worn off my car so I can relax.
Before starting the car, but after turning on the ignition, it reads 12.4. The manual indicates this is the charge in my battery. After warming up the car to operating temp and about 2,000 rpms it reads 14.x.
The alternator light comes on only when the car is running. I keep the car on a battery tender so that would explain the adequate battery charge. The alternator was just rebuilt 3,000 miles ago. Could it be bad diodes or something else that might have been missed with an alternator rebuild?
BY the way someone keyed my new to me 1988 Carrera in two places the other day. Boy am I pissed. I wish I had caught them in the act. I guess the new is now worn off my car so I can relax.
Advanced
Joined: Mar 2007
Posts: 89
Likes: 0
From: Toronto
I'm no expert but I just dealt with a voltage and alternator problem so I'll throw in my 2 cents.
14.x sounds like the right voltage while the car is running. There's a blue wire at the alternator that is connected to the alternator light. I am not sure at what condition the light goes on but you might want to check the wire to see if it is secure.
BTW, I checked with my Porsche dealer about a rebuilt genuine Porsche alternator. He quoted me $330CDN. When I got there to order it, the price changed to over $700. He was very apologetic but there was nothing he could do. But, the parts guy told me to just order a remanufactured Bosch. He said he worked for Bosch and the remans are just as good as the ones you get from Porsche.
14.x sounds like the right voltage while the car is running. There's a blue wire at the alternator that is connected to the alternator light. I am not sure at what condition the light goes on but you might want to check the wire to see if it is secure.
BTW, I checked with my Porsche dealer about a rebuilt genuine Porsche alternator. He quoted me $330CDN. When I got there to order it, the price changed to over $700. He was very apologetic but there was nothing he could do. But, the parts guy told me to just order a remanufactured Bosch. He said he worked for Bosch and the remans are just as good as the ones you get from Porsche.
Thread Starter
Track Day
Joined: Apr 2009
Posts: 24
Likes: 0
From: 35244
The alternator is charging between 13.8 (when I run my Ipod though the stereo) and 14.1 when I do not. The alternator light come on when running and stays on. I have developed a new issue. My tach will stop working and then jump back up the the proper RPMs. It does this off and on while I am driving.
Is there a common link between the alternator light issue and my tach gremlin I should address. I will take a look at all the alternator connections this weekend. Since it was just rebuild 3,000 miles ago I think it must be some kind of loose connection problem.
Is there a common link between the alternator light issue and my tach gremlin I should address. I will take a look at all the alternator connections this weekend. Since it was just rebuild 3,000 miles ago I think it must be some kind of loose connection problem.
Rennlist Member
Joined: Nov 2004
Posts: 4,412
Likes: 148
From: Prospect, KY