I am not sure about 2000rpm at 70mph in 2.5L. My 5sp 190D turning over at close to 3000rpm at 70mph. I suppose the gauges don't lie.

It is a big commitment to collect WVO and to convert it to biodiesel. I think it would consume 4+ hours of your time per week to get the quantity of WVO to go to work. Do you have the time to do it week in and week out?

I think $2900 is a bit pricey for the car without A/C and a broken ODO. The A/C can set you back $800 to 1K easy. I will let others to comment on it.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.