The hoses that pawoSD are referring to go from the passenger's side of the engine, over to the little pump mounted on the subframe rail just below the expansion tank, then up through the partition to the heater valve, which is right next to the battery. From the valve the hose runs underneath the battery tray and to the nipple on the heater core that sticks through the firewall. The buzzing noise could be that heater valve malfunctioning in some way, I suppose, or maybe the aux. coolant pump doing something strange. Another possibility for the buzzing noise is the aspirator motor for the climate control temperature sensor. It's mounted right next to the glovebox in the dashboard.

Another possibility for the coolant coming out behind the wheel: coolant might be overflowing the expansion tank and going down into the overflow tank, which is mounted inside the fender, right behind the wheel on the passenger side. Coolant could be overflowing this tank as well. I would check the coolant for hydrocarbons to see if exhaust pressure is getting into the cooling system. This would indicate a failed head gasket. Unusual, from what I've read, for an m103 head gasket to fail in this manner, but it's possible.

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Streetside: 1987 Mercedes 300E Petrol Blue/Green
2014 Ford Mustang Grabber Blue
1999 Ford Ranger Green

Dockside: 1968 Eltro 17
1985 Silverton 34C