Factory spec 0-100kph (0-62mph) 12.4 secs, they are a little sluggish off the line, but once in boost they go very well. If running correctly. They are difficult to diagnose. Problem is they run OK even if they are not dialed in. You might take it to a Knowlegeable tech and see if they can pull any codes out of the ECM, I believe yours has a seperate altitude compensating servo that the 93 does not have, vacume/digital input into the computer if it malfunctions computer does not give full boost. There are about four pages of diagnosis to run thru, usually a bad vacume servo of one kind or another. once the car is dialed in you will love it. I have owned just about every model of Mercedes diesel starting in 1982 and this series 124 is the best in my opinion. Good luck
1998 E300D sold
1999 E320 AWD WAGON
1993 E300 D
2003 E55
1985 300 TDT
2004 E320 CDI on order