Current draw problem

Leland Pate · 02-10-2006, 05:57 PM

My car has developed a problem with battery voltage in the past few weeks. I started noticing it was cranking slower and slower. I also noticed my battery light on the gauge panel was glowing faintly. Finally I realized it was not the cold weather and that something was wrong because the cranking got slower and the batt. light got brighter. I checked the battery voltage with the engine off and got something like 11.79v. With the car running I got between ~12.4 and 12.6v.

I thought the alternator should be pumping out about 14+v's.

I took the battery to the store where it was bought and ran a dignostic on it. They say the battery is fine.

So I've got a current draw somewhere or an alternator that is not alternating. I replaced the alternator less than a year ago when the old one failed at the track. The battery is also about 13 months old.

What could be the culprit here? A few guys at work said the starter could be the problem.
Any ideas how to proceed with the diagnosis?
_________________________________________
Is there a good way to test the alternator output?

Is there a method to tracking down current draws?

Early_S_Man · 02-10-2006, 06:17 PM

Lee,

A system Voltage that low with the engine running ... is positive evidence of a bad alternator or Voltage regulator, and a sure case for pulling the alternator and taking it in for testing and rebuild! All of our cars need a big, expanded scale Voltmeter ... clearly marked with Yellow from 13.0 to 13.5 Volts, RED below 13.0 Volts & above 14.5 Volts ... and your case is just more evidence!

Wil Ferch · 02-11-2006, 10:40 AM

12.6 volts measured when car is off= 100% charge
12.4V= 75% charge
12.2 V= 50% charge
12.0 V = 25% charge

11.7+ volts is a dead battery.......

Car's charging system should show a range something like 13.3 to 14.5 V or so....

-Wil

304065 · 02-13-2006, 04:54 AM

That will teach you to buy your battery at Victoria's Secret. As capable as they are, auto-electric just isn't their bag, baby!

Your Batterie is kaput, and your Lichtmaschine isn't putting out the right output! Prolly it's your Spannungsregler.

Durn 993's with their complicated electrical systems. No fewer than forty-eight electrical motors in that sucka! Make sure every switch or subsystem gets regular exercise, and keep a spraycan of Corrosion-X handy.

Leland Pate · 02-13-2006, 05:15 AM

lol, or door three... my positive cable to the starter motor had come loose. Tightened it back up and now everything is back to normal.

My father would smack me upside the head for this one. "Always start with the easiest fix and go from there."

304065 · 02-13-2006, 06:52 AM

Odds bodkins. The Porsche G_ds have surely smiled on you, by allowing you to find this before the wire came all the way off the terminal and did its impression of an 880-amp arc welder under your back seat!

Somebody, somewhere was upset about something. Is there another vehicle that is receiving more attention?