Bad alternator????
Thread Starter
Racer
Joined: Jul 2011
Posts: 339
Likes: 6
From: Lompoc California
Bad alternator????
If the car sits for a few days, it acts like the battery is almost dead, but starts. It shows 14.3V on the dash when first started then after it idles for about 10 mintues it goes down to 13.8V. Is this norm, or is it bad alt? Looks like stock alt and has a Duracell battery. I just bought the car a few months back.
Melting Slicks
Joined: May 2014
Posts: 2,895
Likes: 592
From: New Port Richey FL
If the car sits for a few days, it acts like the battery is almost dead, but starts. It shows 14.3V on the dash when first started then after it idles for about 10 mintues it goes down to 13.8V. Is this norm, or is it bad alt? Looks like stock alt and has a Duracell battery. I just bought the car a few months back.
Your Voltage reading you Mentioned Doesn't seem to be shocking 14.5 +- then drops down 13.5 +- in short time Pretty normal
Does the Car have any aftermarket Equipment installed that could be a possible drain?
Last edited by s carter; Feb 13, 2017 at 06:38 AM.
Instructor
Joined: Dec 2016
Posts: 241
Likes: 77
From: Arlington VA
Give all Battery Connections a look at and are free of Corrosion. If the Battery end is Good Tight And Clean and you still have a problem. Disconnect Battery and check other end of Battery Circuit. (Starter and Block Ground)
Your Voltage reading you Mentioned Doesn't seem to be shocking 14.5 +- then drops down 13.5 +- in short time Pretty normal
Your Voltage reading you Mentioned Doesn't seem to be shocking 14.5 +- then drops down 13.5 +- in short time Pretty normal
I'm sure you checked the obvious stuff. Check to make sure the unhood lights go out when the hood is down too.
Pro
Joined: Jan 2003
Posts: 706
Likes: 47
From: Denver Colorado
I believe the next step is to get the battery tested at your friendly Interstate (or what ever) dealer. I used to sell them and they have the standard "bath tub" reliability curve... statistically they fail early in life or they last for a little longer than their warranty period and then fail at a quick rate. My bet is yours is an early loser with a weak cell.
Burning Brakes
Joined: Apr 2016
Posts: 781
Likes: 73
Give all Battery Connections a look at and are free of Corrosion. If the Battery is good and ends are Good Tight And Clean and you still have a problem. Disconnect Battery and check other end of Battery Circuit. (Starter and Block Ground)
Your Voltage reading you Mentioned Doesn't seem to be shocking 14.5 +- then drops down 13.5 +- in short time Pretty normal
Does the Car have any aftermarket Equipment installed that could be a possible drain?
Your Voltage reading you Mentioned Doesn't seem to be shocking 14.5 +- then drops down 13.5 +- in short time Pretty normal
Does the Car have any aftermarket Equipment installed that could be a possible drain?
sounds like alternator and voltage regulator are working just fine. I would start with checking all battery and ground connections.
Last edited by divotdug; Feb 14, 2017 at 06:27 AM.
