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Took the car out for dinner and on the return was approaching a traffic light. Braked as normal to stop but light turned green as I got closer. Stopped braking and downshifted from 3rd to 2nd gear going maybe 20 mph. Upon completing the downshift and before accelerating the car backfired, or thats what it sounded like. I thought it was going to stall but it didnt. Within a mile's distance I noted that my Temp gauge was starting to fog significantly. Although indicated temp was staying between 180-200. Also, I have a voltmeter installed and it was needling like a seismograph during an earthquake. Other gauges were showing normal. I drove another half mile to get home. The next day the car starts as normal but voltage is still swinging wildly. Has anyone else encountered a similar situation?
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I don't think that the two are related unless you are running on an electric fuel pump.

I will bet you a quarter that the car is low on fuel pressure and you were actually running out of gas in the carb when it backfired.

As far as the electric goes I like to do two quick checks with a multimeter.

First with the engine off and cold, measure the voltage of the battery accross the two terminals.

Then start the engine and measure it again with the engine running.

The battery should be recieving at least 13.5 volts. If it isn't, you need to determine if the alternator is producing 14.5-15 volts.

The regulator, if it is operating correctly will vary the voltage to the battery depending on how much voltage the battery already has in it. The higher the batteries voltage, the greater the resistance, the lower the voltage from the alternator.

If it isn't getting at least 13.5 volts and you have checked for corrosion on all the connectors, and you are getting 14.5-15volts from the alternator then suspect the regulator.

My experience with a Pantera is that fuel pressure can drop below 3.5psi with the original pump.
That combined with the fuel pick-up design can lead to virtual fuel starvation.

I like a two pump set up with a carbed engine. A hp mechanical fed by an electrical.
Well, I traced the voltmeter problem to the main (8 gauge?) wire that feeds to the voltmeter. At some time in the car's past, a splice was done - not very well, so the cable was not making good contact with its connector. Re-termination fixed er up. I suppose the backfire and fogging temp gauge were unrelated and they havent recurred.

Cousteau
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