I had been living with a somewhat sluggish 91 300D for some time. Not horrible, but noticeably off acceleration wise. I had long suspected the ALDA, but it's really a pain to get to on the 602 (at least with the tools I have), so I was never motivated to tackle it. Plus acceleration was good enough for most driving.

For whatever reason I decided to dive into today....so I could at least eliminate the ADLA as a variable. My 24mm and 27mm wrenches are long so difficult to maneuver into position. I ended up removing the cruise actuator and the washer tank to get access....and ended up breaking the shutoff valve in the process....OOPS....but JB Weld to the rescue.

Got the ALDA out. WOW! What a HUGE DIFFERENCE! Acceleration is back to exactly where it should be...or at least very close. Really a very dramatic difference.

I know ideally I should shim or adjust...but for now I think I'll just leave it off. Not seeing much black smoke at all.

So, for those of you contending with a sluggish OM602, I would highly recommend that you investigate the ALDA. In my case, it was a night and day difference.

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 157k miles
06 E320 CDI "Rutherford", Black on Tan, 175k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 144k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 70k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife