From the Original Microfiche Plates (North America), dated 1989:
 025 906 022
Vanagon 2.1 2wd & Syncro 86-Early 89 (To Vin 25-K-075000)
 025 906 022D
Vanagon 2.1 2wd & Syncro Late 89-91 (Fr Vin 25-K-075001)
 Later on, Volkswagen superseded the 025 906 022 to the 025 906 022D as a
replacement.
 I do not have info on models outside North America.
 As noted in previous posts "X" following the part number and/or letter
suffix designates the unit as "Rebuilt"
--
Jim Thompson
84 Westfalia 2.1 "Ole Putt"
73 K Ghia Coupe "Denise"
72 411 Station Wagon "Pug"
oldvolkshome@gmail.com
http://www.oldvolkshome.com
**********************************
On 11/10/05, Warner, Jeffrey (Jeff) S (J6C) <Jeff.Warner@dla.mil> wrote:
>
> Okay, now I find myself replying to my own post. I have now read in
> later posts that the X is for rebuilds. Was there not a specific unit
> for the Syncro? From what I recall, one of the units I have is somehow
> labeled differently (a gold label is all I remember) and it was
> identified as being from a Syncro. Guess I'll have to take another look
> at it. The one I tried was definitely a 22D.
>
> Jeff
>
> -----Original Message-----
> From: Warner, Jeffrey (Jeff) S (J6C)
> Sent: Thursday, November 10, 2005 11:37 AM
> To: 'Vanagon Mailing List'
> Subject: ECU: 022D vs 022X vs 022DX ??
>
> Jumping in on this post with related questions.
>
> I have an '86 2WD with original ECU that works fine. A year ago I
> picked up one of each of the other two models (DX and D) as part of an
> engine purchase deal. I tried the D model out to see how it would
> perform. I immediately noticed a much deeper exhaust note which seemed
> to suggest improved performance. I don't recall now whether or not I
> felt that performance on my subsequent test run but about 30 miles into
> that run I experienced Vanagon Syndrome. I managed to get through it by
> radically altering my throttle position until it came around. By the
> way, I was able to see the impact of VS on my OXS gauge. Pretty darn
> handy. Once I got to the camp ground I switched back to the original
> ECU. I now carry this D unit as a spare. Has anyone else experienced a
> perceived change in performance with a D model and is there any reason
> why I can't try the DX unit? I always thought it was specifically for
> the Syncro but now I see here in Malcolm's post that this isn't true.
>
> Thanks for your thoughts.
>
> Jeff Warner
> Galloway, OH
> '86 Wolfy Westy "Barry"
>
>
> Date: Wed, 9 Nov 2005 19:07:17 -0800
> From: Malcolm Stebbins <mwstebbins@YAHOO.COM>
> Subject: ECU: 022D vs 022X vs 022DX ??
>
> I have done my homework and search the vanagon archives AND the yahoo
> syncro lists for the
> differences in ECUs I have found different ones.
>
>
> What is the DEFINITIVE answer to this?? Malcolm
>
>
> BusDepot lists:
>
> Vanagon (2.1 Liter) (1986 - 1992)
> Vanagon Syncro (1986 - 1992)
>
> http://www.bus-boys.com/bb13386.htm#4
>
> 025-906-022X 1986-1987 2WD
> 025-906-022DX 1988-1991 2WD, 1986-1991 Syncro
> 025-906-022D New ECU 86-91 All Models NLA
>