64 Newport- Fuel Gauge internal regulator

OG Velvet

New Member
Sep 5, 2018
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Portland, OR
Beaten to death subject- I know... I am brand new to Mopar. Bought a 64 Newport from my Dad about 6 months ago. Fuel and Temp gauges just went out.

What I know...
  • The voltage regulator is internal in the fuel gauge
  • Both senders work
What I need to know...
  • If I get an aftermarket fuel gauge, can I hook up an external VR to the original temp gauge?
  • Can I bypass the internal VR, use an external VR and use both original gauges?
Thanks in advance!

mr. fix it

Old Man with a Hat
Aug 14, 2013
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Check your grounds first.
They can be repaired.
Have a look around on the previous threads under the electrical forum here.
There is info on Google as well.
That's a good question about the external VR to make the temp gauge work.
Can't say I have seen anyone post about that trick.
And a big welcome as well from Niagara Ontario:canada:


Old Man with a Hat
Mar 27, 2011
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Howdy and welcome!

I believe what you're terming "voltage regulator" is more aptly termed "voltage limiter" as it limits the voltage to the gauges to something like 5.5 volts, rather than a full 12 volts.

Look at the factory wiring schematic to see where the voltage "feeds" for those two circuits are. It's possible they are fed from the same source. Provided that the related grounds for each circuit are good, finding the issue with the voltage feed could well fix the issue. It could well be a wiring issue behind the instrument cluster down to the fuse block.

The temp gauge should be a "direct" wire, I suspect? I suspect you have already checked that wire between the temp sensor on the engine to the bulkhead connector and then to the gauge itself? I san "sensor" as "sensors" vary voltage to the gauge as "switches" are for warning lights, although both are classed as "senders".

Everything depends upon "grounds" being good and solid. Any added resistance in those connections can result in skewed readings of the respective gauge.

It seems that many people get in trouble trying to wire around factory wiring as it might seem to make sense to them to do so. Just use the existing architecture and put it back to "as produced" configuration. That's usually the best way to do it, in the long run. There might be a few exceptions to that rule, but they can be few and far between, by observation.

There are later model voltage limiters which are solid state rather than "vibrating points". They were used on '80s Chryslers, I believe, as OEM. I believe you can find some in replacement vendor sources, too.

Just some thoughts,