Went for a successful test drive tonight and I seem to have all the leaks plugged up, and all of the old oil burnt off. While driving, I noticed that my voltage really drops when I have the lights on, and even after I pulled into a parking lot to stop for a while, the gauge showed lower than 12 volts. I am concerned that I either have a short in my lights, or I just have a weak/dying alternator. OR I could just be too worried about something that isn't a problem at all. Any suggestions form the crew here?
Jim
Full Version: Voltage drop
QUOTE(BiG bOgGs @ Dec 16 2007, 04:52 PM) 
Went for a successful test drive tonight and I seem to have all the leaks plugged up, and all of the old oil burnt off. While driving, I noticed that my voltage really drops when I have the lights on, and even after I pulled into a parking lot to stop for a while, the gauge showed lower than 12 volts. I am concerned that I either have a short in my lights, or I just have a weak/dying alternator. OR I could just be too worried about something that isn't a problem at all. Any suggestions form the crew here?
Jim
What brand gauge OEM or aftermarket.
I wouldnt trust the OEM if its not new
Use another source to test your voltage. Elimnate the possiblity of bad gauge
The factory gauge in the center console is not accurate. How it is wired in cause's the needle to drop or fluctuate when consumers are turned on. Very useful to remind you when you've left your turn signal on. 
Wouldn't hurt to check the voltage at the battery with a good meter to be sure everthing is ok.
Wouldn't hurt to check the voltage at the battery with a good meter to be sure everthing is ok.
QUOTE(BiG bOgGs @ Dec 16 2007, 05:52 PM)
Went for a successful test drive tonight and I seem to have all the leaks plugged up, and all of the old oil burnt off. While driving, I noticed that my voltage really drops when I have the lights on, and even after I pulled into a parking lot to stop for a while, the gauge showed lower than 12 volts. I am concerned that I either have a short in my lights, or I just have a weak/dying alternator. OR I could just be too worried about something that isn't a problem at all. Any suggestions form the crew here?
Jim
I had the same problem with a 73 2.0 I had. Simply a case of loose and dirty battery terminals. Hope yours is equally simple. Another possible cause is a loose alternator belt.
Sorry I didn't give more info. I have a 76 2.0, so the gauge I am speaking of is the factory center console gauge. I will check the voltage directly, and check the alt belt as soon as I can. Thanks for the quick responses.
Jim
Jim
Having the needle drop is normal. How much is more complicated...
Pretty common.
The voltage read on the gauge is inaccurate. Tap it into an accurate source... such as right on the battery.
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.