 Voltmeter reading? Accuracy? |
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| SKL1 |
 Jan 5 2026, 09:52 PM
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#1
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Senior Member  Group: Members Posts: 1,744 Joined: 19-February 11 From: north Scottsdale Member No.: 12,732 Region Association: Upper MidWest 
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Trying to figure out how accurate the OEM voltmeter is in my '73 2.0. To make a long story shorter the engine in the car is a much modified 1.9 from my '71, with approx 120K miles on the alternator.
Voltmeter reads around 11V and drops to 10 if I turn on the headlights. Immediately goes back to 11 or just over that with the lights turned off. Replaced the voltage regulator this AM and did a test drive with no change. Gauge never gets close or above 12V. Makes me afraid to drive it at night with the lights on and go very far. Do I need to go through the hassle of rebuilding the alternator or trying the alternator from the original 2.0 engine that has about 70K miles on it? Better way to get a more accurate reading of actual voltage?? I hate electrical issues!!!! TIA. |
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| mjrrti |
Jan 5 2026, 11:16 PM
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#2
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High Desert Member Group: Members Posts: 56 Joined: 4-February 14 From: Apple Valley, Ca Member No.: 16,959 Region Association: Southern California |
QUOTE(SKL1 @ Jan 5 2026, 07:52 PM)  Trying to figure out how accurate the OEM voltmeter is in my '73 2.0. To make a long story shorter the engine in the car is a much modified 1.9 from my '71, with approx 120K miles on the alternator. Voltmeter reads around 11V and drops to 10 if I turn on the headlights. Immediately goes back to 11 or just over that with the lights turned off. Replaced the voltage regulator this AM and did a test drive with no change. Gauge never gets close or above 12V. Makes me afraid to drive it at night with the lights on and go very far. Do I need to go through the hassle of rebuilding the alternator or trying the alternator from the original 2.0 engine that has about 70K miles on it? Better way to get a more accurate reading of actual voltage?? I hate electrical issues!!!! TIA. I just bought a cig lighter usb charger on Amazon for about 9 bucks. It has a digital volt meter built into it. I bought it for usb use but it reads the same as the aftermarket sun pro voltmeter I have in my car. Should give you a good idea of where your factory gauge stands. I don’t know how to attach a link but here is a pic.  |
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Posts in this topic
SKL1 Voltmeter reading? Accuracy? Jan 5 2026, 09:52 PM
mjrrti The brand didn’t show in my pic but it is zeehoo... Jan 5 2026, 11:22 PM 930cabman I have found voltmeter readings somewhat erratic, ... Jan 6 2026, 05:58 AM emerygt350 It's really not the voltmeter, I checked mine ... Jan 6 2026, 06:36 AM GregAmy
Trying to figure out how accurate the OEM voltmet... Jan 6 2026, 08:15 AM
SKL1 Thanks. The meter in the lighter sounds great but... Jan 6 2026, 11:47 AM |
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