Voltage gauge question, Volt gauge is jumping and lights are dimming Options

[Vanilla133]

Hello everyone...this is my first post but I have been on this site every night for the last 3 months trying to learn more about my 914. I have searched for info on my latest issue but could not find the answers I was looking for.

I noticed tonight that the headlights and dash lights would dim sporatically and the volt gauge would jump at the same time. Normally the gauge would twitch when the turn signal is on but this is the first time I have noticed it jumping or spiking and the lights dimming.

Is this normal?

Btw...I have a 75 1.8.

[southernmost914]

Could be 1 of 100 things, but lets start by checking that your grounds are clean and tight. Check your battery and transmission grounds, headlight grounds. Start there (IMG:style_emoticons/default/biggrin.gif)

Steve

[Spoke]

(IMG:style_emoticons/default/welcome.png)

First off, information here isn't free. We need to see pics of your car. Otherwise someone will hit you with a

(IMG:style_emoticons/default/thisthreadisworthlesswithoutpics.gif)

For the most part as was just mentioned, you need to start finding the ground terminals and cleaning and tightening them. Also check battery terminals for cleanness. Remove the terminals, clean and replace.

Of the could be items, it could be your grounds, the voltage regulator, or dirty fuses. Also behind your fuse panel, there is a big lug on the chassis that brings +12V from the battery. In my car, this had worked loose. Before you lower the fuse panel, disconnect the NEG terminal of your battery so in case you cross some wires you don't hear the pow or bang when wire fry themselves and cause you lots of extra work.

[marks914]

It sounds like your voltmeter is working properly, its letting you know that there may be a problem.


2.Start with the obvious, condition of battery, clean terminals, alternator, stc.

Mark

[jim_hoyland]

I had the same problem when I got my '75 1.8 I changed the + wire attachement from the brake light switch to the fuse panel ( It was along time ago ). You may want to see where the voltmeter is getting its signal...

[Vanilla133]

Thanks for all of the replies. I will start with checking and cleaning the grounds. The battery and cables are all new and tight. I just finished a 3 month refurbishing of the car. The PO had the car since 1978 and had all maintenance history and receipts. It was all original with minimal rust...found out there was much more rust once I starting tearing it apart. This one is my third 914 but I didn't keep the first two long enough to learn that much about them. I did change out the oil cooler seals with the engine in the car...pretty easy and only took a couple of hours thanks to the info from this forum!

I will post pics soon...still adding a few finishing touches before I debut her on here.

Thanks again!

[SGB]

When my volt gauge started going wa-ay up I thought it was voltage regulator, which I replaced. It fixed it- for a short while, then away went the volts again. I ended up replacing the alternator and voltage regulator- and all is well now.