This will be my last post on this subject.
I hope you enjoy your W124, I'm sure you think very highly of the car. They are nice cars, I still own two of them.
You realize, of course, the number you cited above from wike is for a constant 53.8 mph? Do you really drive like that in the real world?
I really don't care to try to defend my observations to you. It's not important to me, and I've already told you what I have observed. For me, it is a game to see how high I can get the mpg number, and I am constantly aware of what the car is achieving at any given time (thanks to that wonderful computer that you hate). I'm not into hypermiling, just comfortable travel. My wife drove 50% of the outbound AND return trip, and she is not one to be concerned with overall mileage. The fact that the CDI can generate these MPG numbers without even trying hard is quite impressive. I'm not going to quibble over a slight variance with calculated vs computer, I only reported my observations of the computer.
My numbers have been reproduced by others, they are not at all out of line with what I can reproduce on the car at any time. It is what it is. You may choose not believe it, as others no doubt question your observations on your own car. I'm not the unaware typical owner. I'm an engineer trained to look at facts without emotional bias, and I've been wrenching on cars for over 40 years.
You paint with a broad brush the inaccuracies of the computers. Have you ever driven a W211 CDI for any distance? I've put 14K miles on mine so far, and I know for a fact that the computer is very consistent and close to my calculated mpg. As I said, close enough that I stopped trying to log every fillup. I have 8 cars/trucks, I don't have the time or inclination to go bat-sh** anal on each one. I can reproduce these numbers, and so can my cousin. That's a cumlative 64K on CDIs. I'm happy with my mpg, and I was very pleasantly surprised to see an observed high mileage number based upon a 500 mile trip at relatively high speed with aircon running the entire trip.
I sure didn't expect to get accused as a charlatan when I posted the results. Looking at your postings, you appear to revel in taking an antagonistic approach to any idea you do not personally subscribe to. If, indeed, you can get your claimed mileage out of a W124 300D, imagine how much more you would get from a W211 CDI. Why I bet you could outdo my results, easily. Why don't you drive one and find out firsthand what amazing cars these are? Given some time to understand how these cars work, I'm sure you could do much better than my cousin and I can achieve. My car didn't deliver these mpg results when I bought it, I've spent some time tweaking it to max out the numbers, so I don't expect every CDI to achieve the same mpg. Remember, your mileage may vary....
The W211 CDI is a modern marvel. It is so far beyond the W124 chassis it's not even a fair comparison. Spend some time in one, you'll be seduced. I was.
Regards,
Jim