My 1993 300ce has an erratic water temp gauge. It reads normal then shoots
up to the highest point in a flash. If I tap the gauge with my hand it comes down to normal. This happens continiously during my drive.The gauge is part of my (fuel gauge assembly) Water,Oil & Fuel. I was told by a non-mb dealer
that it was the gauge itself and that it would have to be replaced at a cost of about $400. I was hoping that it could be a faulty ground wire behind the gauge itself. Are there any other members with this problem. I would appreciate any input here. btw: The fuel & Oil gauge readings are fine.

Thanks, Rick