1991 Questions for all other cars electrical problem

1991 ALL OTHER MAKES ALL OTHER MODELS
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TAIP
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Electrical problem
1991 Questions for all other cars 4 cyl Front Wheel Drive Manual 50 000 miles

hi there,
it's about yugo 45 (900cc) based on fiat 127. here's the problem: when car is at idle 850 rpm, and whenever i put on brakes or the radiator fan starts blowing, the idle decreases to 600 rpm and it starts to misfire. there are 4 x 21 watt bulbs for brake lights. Also while i cruise, and turn on the headlights the car immediately loses a slight power i can feel it. can it be due to a bad battery? because in summer after a long journey it doesn't hold the charge and it won't start the engine (no noise coming from the starter but the control lights fade). I don't face these problems in winter. the battery voltage reads 12.45 all the time and it starts to drop gradually as i turn on any car accessory. can this affect the ignition coil? sometimes car runs smooth as silk... i'll go crazy. thnx a lot.
Aug 20, 2009 at 3:03 PM
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MERLIN2021
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If voltage drops as you turn on accesories, then the voltage regulator is probably the problem, Yugo alternators I am NOT familiar with, it may have an internal regulator, if so, the alternator needs changing, this would be tru in hot or cold weather. Autozone will test your system free...more info here..
https://www.2carpros.com/how_to/how_to_test_alternator.htm
https://www.2carpros.com/how_to/battery.htm
Aug 20, 2009 at 3:16 PM
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