Alternator or Voltage Regulator?

[Puma]

Hello,

Today whilst driving my battery light came on, then it wouldn't start, got a jump, drove two blocks, rpm fluctuating wildly, spoiler came up while traveling at zero miles per hour, air bag light came on, dash lights flickering. Removed the battery and had it tested: PASSED, guy said there wasn't enough power to test the alternator (he was very intimidated by the word Porsche).

I've never had a voltage regulator fail so I don't know what it's like. I've had alternator fail and jumped it and been able to get where I needed to go, but this seems very different as the car dies after only a few blocks.

Can anyone shed some light?

Thanks in advance,

Puma

[DRACO A5OG]

If you have AAA, call them out they will check you entire system and give you a read out.

If alternator is shot the battery will power the plugs until it drains out. Ask me how I know.

[Puma]

I don't have AAA, I gave it up ten years ago because I never used it.

Can I perform a test myself with a voltage meter?

[DRACO A5OG]

Nope you need a reader to measure AMPs.

I know what you mean I never used AAA so much until I got my 911. Always had leased cars.

Well I take it back my '66 Mustang used is a bit too, since I was 18.

[twin plugged targa]

You may wish to post your car type/model/year
If you have a volt meter, you may wish to take some voltage readings across the battery terminal posts (not the connectors) at idle revs and at 3K revs
Post your findings
Check basics:
Battery connections are tight and free of corrosion
Battery earth strap is secure and clean at chassis end

After the basic information is listed some might be able to better help you here-

Doctors always need symptoms and patient prior history for better diagnosis!

Hopefully someone here can help you
rgds Ben

[Joe Bob]

Fully charge the battery. Put a meter on the terminals.

12.5 at rest
13 at idle
13.5-14+ at 2500 rpms

Anything less, is a suspect alt, more usually the VR.

[stevie 77 930]

" spoiler came up while traveling at zero miles per hour, air bag light came on, dash lights flickering" .....


Sounds like you are on the wrong forum. No air bags or movable spoilers on these cars. 993 or 996 perhaps ? In either case, being a later model, the voltage regulator is in the alternator. Replace the alternator and you should be done.

[twin plugged targa]

"- no airbags or moveable spoilers?"
964, 993 and 996's are all 911' s and have airbags and spoilers which raise and lower with speed variations.
- or was that subtle humour that i missed?

[stevie 77 930]

humor

[Puma]

I have a 2001 Boxster tiptronic. I posted the question in that forum and received no reply.

Because voltage and alternator problems/systems are probably the same I posted it here as well hoping to find some answers.

[rnln]

huh uh ummm... the internet world is sometimes confusing. I am with Stevie, would think people in 964/993/996 would know more, if his car is one of those. Right?

Originally Posted by twin plugged targa

"- no airbags or moveable spoilers?"
964, 993 and 996's are all 911' s and have airbags and spoilers which raise and lower with speed variations.
- or was that subtle humour that i missed?

[Joe Bob]

Probably 'cause most 986 owners fix their rides with a check book....

[Targalid]

Puma,
I had similar symptoms on my 76, several decades older than your toy. I got myself a cigarette lighter voltage meter so I could monitor the charging system: Vector brand, digital readout. Then I charged the battery and drove the car while watching the voltage readout. I then went through the engine compartment checking each and every connection, then driving the car or simply starting the motor to see if there was a change. I traced it to the voltage regulator, a French manufacture Marichal. I figured out how to disconnect the little devil to get the numbers from it so I could order a replacement from Pelican and while doing so cleaned all the connectors. Voila as the French say! It worked! The voltage readout changed from 12.3 volts to 14.0. I am now driving a car with a trouble free charging system. Good luck! Maybe your problem is as simple as a corroded connection.

[tcar]

Originally Posted by Puma

I have a 2001 Boxster tiptronic. I posted the question in that forum and received no reply.

Because voltage and alternator problems/systems are probably the same I posted it here as well hoping to find some answers.

ALWAYS post the year and model of the car in the original post, man.

Even 911's have differences from year to year... not to mention your 'new and improved 914'.

[DRACO A5OG]

Sorry Puma, we are just trying to help.

We find it very difficult o diagnos with out info, that's all.

Anywho, I still say reactivate AAA, it is better not to need it but when you do, it will save you.

I had to tow my baby 70 miles to a shop. AAA Premium, FREE