I turned back my ALDA to original spec and got 22.55MPG. With 1 full turn CCW I got 23MPG (lowest), sometimes 24, sometimes 25. I wonder how my turbodiesel fares with your turbodiesel (W123 only) in terms of fuel economy. Any other things I could do to increase fuel mileage?

Best I could do was 27MPG. I've done Diesel Purge alongside changing fuel filters, both pre and main, but didn't use up an entire can. Maybe 75% of it. Should I pour that Diesel Purge into a near empty tank and let it run until the "R" light goes on?

Will adjusting the turbo wastegate increase fuel economy? I believe I have the Garrett type. Also does the type of turbocharger affect fuel economy? Others have KKK but I heard perform differently on both city and highway.