I have a 2000 model C230 Kompressor with 109K miles. I live in CA. I don’t drive but 4K miles a year. I’ve had trouble passing the catalytic converter smog check the last 3 times it has been required. The mechanics tell me that I’m not driving enough freeway miles. All other checks of the smog test pass with easy. Any suggestions? I Love this car and it has so few miles.