Voltage Drop and Missfire

[David Maddern]

I took the Stag our for a spin yesterday as it was a nice day, all was very good, until the motor gave a splutter and started to misfire, lack of power and some very worried thoughts.

I noticed the voltage indicatorhad dropped to about 10 volts, which would have explained the missfire and within a couple of minutes the voltage reading steadily raised back to about 14 volts and all was fine.

I got home and did the usal look around the battery terminals, the alternator leads and the voltagestabaliser box and all was well, I cannot decide if I have a bad battery, an alternator on the way out or the voltage stabaliser on the blink.

Hasanyone out there had a similar experience or perhaps could give me some indication as to what would fix this, I would be gratefull for some help.

[Guest]

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Hi David, difficult to tell from a distance, but it sounds like a failing alternator, have you got a multimeter to check it and the battery ? If not, that's a fairly good bet. Martin.

[V Mad]

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David Maddern wrote:

I took the Stag our for a spin yesterday as it was a nice day, all was very good, until the motor gave a splutter and started to misfire, lack of power and some very worried thoughts.

I noticed the voltage indicatorhad dropped to about 10 volts, which would have explained the missfire and within a couple of minutes the voltage reading steadily raised back to about 14 volts and all was fine.

I got home and did the usal look around the battery terminals, the alternator leads and the voltagestabaliser box and all was well, I cannot decide if I have a bad battery, an alternator on the way out or the voltage stabaliser on the blink.

Hasanyone out there had a similar experience or perhaps could give me some indication as to what would fix this, I would be gratefull for some help.

You can forget aboutthe voltage stabiliser; this only feeds the temp gauge and fuel gauge.

Since the voltmeter showeda drop in voltsat the same time the engine spluttered, the most likely fault is with the main 12 volt supply system ie the battery and alternator. The battery and its connecting leads are most likely at fault because even if the alternator stopped charging momentarily, the volts should not drop that low. At 10 volts, it sounds like one cell of the battery went down for a moment, orthere is a badbattery connection.

[Malcolm C]

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David I have a multimeter and only live about 2 miles from you.
Your more than welcome to pop over
Malcolm

[colin hanney]

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Hi David check all the earth connections from battery to engine you never know.Hope this helps Colin H.