The early Omni/Horizons came with a gasser inline 1.7L VW longblock. 
I'm not aware of any diesel engines in that series vehicle.

On 2/9/06, Matthew <mpteleski@yahoo.com> wrote:
> just got a weird phone call... so, will a dodge omni
> engine fit in a vanagon? the guy (who i know, but i
> know he doesn't know vanagons) says it is a direct
> bolt up. he was not sure on the year ("either a 82, 3
> or 4"), so could be a wasserboxer or diesel. it is
> watercooled he says.  he is sending me photos, but
> until then, someone fill me in on this. a quick google
> did not show much.

Casey
Olympia, WA
Biodiesel: "I drive in a persistent vegetative state"
'87 300TD intercooler (211k)
'84 300D (210k)
Gashuffer:
'89 Vanagon Wolfsburg Edition (187K)