Wife and I own a 1989 420 Sel Mercedes Benz. Beautiful Car. Just past smog and get 22-23 Hwy miles per gal. Wife loves this car. The car has never idle smooth. When we got a last tuneup,mechanic told us his brother owned the same model and his did the same. Is this true for this model year. We took car into Mercedes benz and service manager is telling me at 229,000 currrent miles we should think about buying a new engine or buying a new car. Its my understanding these cars are built to last 500,000 miles, what is he talking about. Telling us the stainless steel timing belt might be a little lose and thats why the car is not idling properly. I'm confused.
