PeachParts Mercedes-Benz Forum - View Single Post - 1993 w140 300sd transmission sluggish forward and reverse. What to look for?

JHZR2 · #2 03-08-2022, 01:14 AM

Hard to say without driving it. The w140 is a big, heavy car, so it could be nothing. My 1991 350sd and my 1993 300sd, both with the OM603.97 rod bender engine drive quite different. The 600lbs in the w140 makes a difference, even for the 3.5L 603.

A lot of throttle doesn’t mean much, and again could be normal.

First and foremost I’d want to know if I’m getting boost. Do you know how to pull codes on this car? Go on eBay and buy a $38 code reader led box… understand the edc codes especially. The. Start figuring out about boost. Have any? Enough? Ideally install a boost gauge via the nipple on the manifold and a three way rubber fitting. There’s a good chance thst the vacuum operated wastegate is affecting boost and thus slowing things down…

How are the fuel filters? Once driving at speed on the highway, will it do 80MPH with ease on flat land? Any smoke?