Could be the sign of an alternator fading away-keep an eye on it, and ensure you have a strong battery in case it fails-a strong battery will keep a car with no alternator moving for at least a short ways, but this is rough on a lead acid battery

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"If God had meant for us to walk, why did he give us feet that fit car pedals?" Sir Sterling Moss

Michael
2014 E63S Estate
2006 SLK55
1995 E500
1986 Porsche 944 turbo