Now that I have switched back to the 280SE for daily transport, I thought it might be due for a major tune-up. Performance is certainly 'softer' than it used to be, and fuel economy isn't that great. I recently replaced plugs, all fluids and filters, and set the valve clearances, ignition leads, cap rotor.
Now, this engine was rebuilt at an indicated 257000km (at the time it was suspected that the true mileage was 50 000 to 100 000km more). Fuel injectors were replaced at about 290...