My wife's 86 300e ends up with a low battery from time to time. I put it on the charger and it recharges fine. Then in about a week I have to do it again. I have checked the voltage at the battery when the car is running and I read 13.3 to 13.5. All lights and AC on full it drops to 13.2 to 13.4. The battery is about 6 months old. It almost seems that 13.3v is not enopugh to fully charge the battery and over time it slowly looses its charge. I have changed the voltage regulator module and the voltage has not really changed much. I was assuming that maybe the old regulator would fail intermittantly, from heat or something and it would quit charging altogether. Does the voltage im reading sound high enough to fully charge the battery. It is my understanding that 13.8 to 14.4 volts is what is required to fully charge a battery.

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I got too many cars!! Insurance eats me alive. Dave

78 Corvette Stingray - 3k
82 242 Turbo Volvo - Manual - 270k
86 300e 5 speed manual - 210k
87 420sel - 240k
89 560sl - 78k
91 420sel - 205k
91 560sel - 85k
94 GMC Suburban - 90k
97 Harley Davidson Heritage Softail - 25k
00 GMC Silverado 1 ton 30k