Got an offline question about ESP. It's the traction control/stability control program. Our E300D had ESP, and it didn't do much for me. ESP cannot preclude the laws of physics, and that includes traction. The best tires are the real answer.
The W202 cars had some early problems, but they're minor. The 94-95 cars have the wiring harness issues that afflict the W202 and W124 cars. Once replaced, it's fine.
The 1996- cars have the variable pressure AC systems that work very well, and component life seems long. There are some evap temp issues that are MB wide (W140, W202, W210), but thankfully it's a simple and fairly inexpensive repair.
Air Mass Meters are problematic on all OBD-II cars, and that includes non-MB cars. Tough to find a maker these days that isn't struggling with AMM problems, MB included. The W202 part for 1997 cars is expensive for an MB AMM, but cheap compared to Toyota or other makes.
W202's driven on bad roads can wear lower front ball joints quickly. W210's do this too.
The 1997 and 1998 722.6 equipped cars have some transmission issues, but in many cases, easily solved. Conductive plates, valve bodies and pressure control springs are common failures. Electronic Tranny Controls also should be updated. My own tranny suffered from pressure control spring failure, which causes a hesitation of idle. The dealer talked MB into a whole new tranny and software.
Final drive seals can sweat, common to W202 models.
Cruise control seems to finally be sorted out by VDO, and works very well. It even downshifts on hills (up and down) to maintain the set speed. Very precise. On my W201 cars the cruise was broken long before this point.
I have owned several new cars that I have driven to 150,000km's. None were as durable and as "like new" as the C230 at the same age/mileage. The M111 2.3 aspro engine continues to amaze me. We went to the Rockies and back in September and I averaged 6.8L/100km's on the trip. That's about 37mpgUS. At 150K-km's (about 95K-miles) it has yet to use a drop of oil, and runs like brand new. With the exception of a panel of MB Tex on the driver's seat cushion (now repaired, and looks new) the interior looks like new. It's tight and the car drives perfectly.
My car is a Canadian model and lacks some of the gadgets of the US versions. I have no traction control at all, and don't miss it. I use premium snow tires (going to Hakka 2's this year) and drive through some really tough conditions. I also have fully-manual seats, no power driver's controls. Suits me fine.
Since we're coming to the end of my warranty (160K-km's) the dealer ran a compression test last month and found all four cylinders at 11.5bar (167psi) which is exactly the same as found at 60,000kms. Right on "new" spec. The M111 is a DOHC design and uses a double-row timing chain that should be very long-lived since it has a short, direct, path. I know a few M111 owners that are at 300K+ and their engines are tight and strong.
If the AC system holds up and the new tranny is as sorted out as some claim, I see no reason why I can't make 400,000 plus kilometers. It will cost some cash in routine maintenance, and I know some repairs will crop up, but overall the C-Class is the cheapest cost-per-mile car we've owned, and I expect that to continue as the odo rolls on.
Things I don't like? Well, the mono-wiper is not to my liking. Just not enough clearing ability in the rain at night. The shifter gate has 4-3-2 on one plane, not like older MB designs and discourages manual shifting. All the windows have "one touch" up and down, but the sunroof does not. The glove box is tiny, but that's thanks to the airbag. The console storage is a decent size. By 1998, it was pretty much accepted that high-end cars had CD players. I HATE trunk mounted changers, and there's no OE in dash CD.
1998 C230 "Black Betty"