US only
1.5L NA - 1981 and before
1.6L NA - 1981 - 1991
1.6L Turbo - 1985 - 1986?
No diesels in 87,88, and 90
1.6L Eco Turbo 1991-1992 (only diesel in 92 from what I have read)
No diesels in 93, 94, and 95 (transition between normal diesel to LSD (500 ppm))
1.9L TDI - 1996 to 2006
Transmissions are mainly 5 speeds with different ratios, very few automatics with diesel. I prefer the AOP or the AGS tranny. Here are the transmissions and gears:
http://www.scirocco.org/gears/Eco diesel is a Turbo Diesel without the enrichment on it, basically a 1.6 NA with a Turbo but with a turbo block.
This info is what I understood to be correct.