Judging by your symptoms, I'd say that you don't have it. The afterglow results in a smooth start under just about every condition.

The 350SD might be the W140..........it might be the point of the changeover.

Actually, the symptoms I have are not really at startup. The car typically starts up very smoothly with just the typical diesel sounds for a few seconds until everything gets moving in there - the rough idle doesn't really start until after the car heats up and has been running for a while. I just tried the extended glow period to see if it made any difference. Actually, the rough idle has become significantly better since I started running 100% WVO.

I'm pretty sure I have a funky injector - if it is idling rough at a stop light, I hit the gas pretty heavy when I take off, a little puff of black smoke comes out, and then it runs smoother.

http://mb.braingears.com/124_DISC1/Program/Engine/602_603/15-0705.pdf

Check out the application chart toward the end of the chapter. I know the dates aren't accurate as my 201.128 from 3/87 has afterglow and the chart says otherwise, unless, like all things with US models, it was an 87 in Europe and an 88 in the US, much like my 124.133 an 87 by model year, but built in 6/86 without afterglow.

__________________
Mark
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THE WHITE FLEET
2016 GLE300d 4-MATIC 38K BROWN!
2012 S350 Bluetec==94k WHITE

2007 ML320 CDI==166K WHITE (FOR SALE)

Under new management:
2005 E320 CDI--140K--WHITE
1995 E300-Diesel-133.5K--THE CAR IS BLUE
1986 300SL--97.5K (European) AND WHITE. Back in Europe!
1991 190E 2.3-73K California Perfect.--WHITE
1995 E320-Wagon-159K--WHITE (recently scrapped)
1987 300D Turbo-213K--WHITE
1987 190D 2.5 Turbo-288K--WHITE

The chart confirms that the W126 has no afterglow in the '86-'87 model years.........that arrived in '90.

Or if you don't want to wait just stab the throttle a bit and blip it up to 2k-3k rpm. I can feel mine starting that skipping crap once in awhile and I just give it a bit of throttle she smokes and clears her throat.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

After I installed my GC kit, my SDL idled like sh** once it warmed up just a little bit. Seemed that something in electronic controls switch engine into a different regime.

Replacemed nozzles with bosios and 500 miles of break-in and this problem went away. Ran like a top, no more crappy blue smoke when engine got a bit of warmth and was super smooth.

__________________
1982 300TD 210K miles ("The Replacement" aka "The Anvil") - SOLD
1979 300SD 245K miles (never ending project)
2007 Pinarello F3:13
1995 Ducati 916 (SOLD, sniff)
1999 Ducati 900SSie (SOLD)

I ran my 350SD for a little while again this morning while I ran some new WVO into my tank... I decided to try switching to WVO again, so I hit the throttle up to about 3000rpm and flipped the switch. It stuttered just a little, then kept running on WVO.

I know the system is still not set up exactly right, so I'll be taking it to my mechanic tomorrow morning, but I still decided to take it out for a drive since it was running successfully on WVO.

Again it ran very well with lots of power, acceleration, and very little smoke. The idle was pretty darn smooth, and overall I'd say the performance was not lacking at all. I went out on the freeway and drove speeds up to 90mph and everything was running great. I did feel one little moment that convinced me that my problem is definitely with fuel supply on the WVO side - it stuttered a little bit under acceleration, exactly like my VW did when the fuel filter was clogging up. I know it's not a filter issue - just a fuel supply issue in general, so I should be able to get to the bottom of it pretty easily.

Anyway, I'm looking forward to getting everything running exactly as it should so I can drive it all the time!