B3 AAZ tech info

[Vincent Waldon]

My guess is it's for boost enrichment.

Your pump has no boost enrichment capability however (no LDA), and on pumps that do it's straight analog pressure feedback directly from the intake manifold (the small hose that's capped off in your first picture) as opposed to thru a controller valve.

Where does the hose that's connected to the fast idle servo go?

As an aside, I was on the Bentley site the other day... yah, need a life... and noticed that they publish an electronic manual that covers the early Canadian AAZ:

http://www.robertbentley.com/vw/passat/1990-1994/VW-Passat-Repair-Manual-1990-1994-Download-eBahn.html

Gonna be spendy though.    :'(

[Big Daddy Roth]

Ok, it's for 'fast idle'. Cold weather and A/C.

I still don't know what the limit switch on the throttle plate is for.

It's been suggested to me to swap the pump for one with the LDA anyways.

I'm going to rebuild this engine. What other swap parts will I need? TDI crank and pulley? Where can I buy a set of good pistons and rods? What turbo can I upgrade to?

[Big Daddy Roth]

I think I got it figured out.

The limit switch just cuts the fast idle when accelerating.

I bought a mk3 AAZ injector pump today. I'll swap it in when I rebuild the engine.

[72panelvan]

Unfortunately there's no LDA mechanism or drillings under that cap... so the only way to add boost enrichement is to swap out the top half of the pump.

I've got this economy same pump, is it simple/straightforward to swap over the top half of the pump? does anyone know of any schematics which show what's required from the LDA pump?