B3 AAZ tech info

[Big Daddy Roth]

ETKA tells me that module is for the EGR. It also tells me that my passat has one. What it doesn't tell me is where it is. It's not in the replay panel.

As for the glow plug relay. I think that take the place of the fuel pump relay, no?

[carrizog60]

my passat had the same engine...
switching to 1.6 gtd pump and 1.9D engine but what to do with the connectors that were on the old pump?

[homerj1]

Clarification please. What does the black thingamealie (pictured below) with 2 vacuum lines and an electric connection, located on the pass. side inner wheel well do?

Can it be removed?

thanks

[Big Daddy Roth]

I'm pretty sure that's for the EGR valve

[Vincent Waldon]

In my mind it depends what it's connected to.  

That's a generic vacuum valve so it can run a bunch of different vacuum actuated stuff:  the EGR valve for sure, but on cars so equipped it can also run the turbo or the fast idle.  My 94 has a couple of those bolted near that spot.

When you trace the vacuum hoses where do they go?  One side will likely go (eventually) to a source of vacuum ie the vacuum pump, and the other side will go to what it controls.  "Where it goes" will help you understand if it can be safely deleted.

[homerj1]

Thanks, I guess it is time to start some detective work 

[Henchman]

Is it possible for the intake air pre-heat system?  Sucks intake air from just beneath turbo until coolant warms up and then a flap in the airbox switches, pulling air from leading edge of hood?

Ian

[Big Daddy Roth]

I did some following of the vacuum lines.

Why is there a vacuum line running through the firewall right where the heater core lines go in?

[Vincent Waldon]

It actuates the diverter flap on the heater box inside the cab.... "fresh air" vs. "recirculate" I believe.

[commuter boy]

2) The air filter housing looks like it *had* cold air preheat... the big corrugated tube at the bottom of the picture goes to a tin shroud over the exhaust manifold.  A vacuum-actuated flap inside the air filter housing(which is what the hoses are for) gives the engine warm air under cold conditions.  I've actually never seen one on a diesel... that and the MFA are making me wonder if your car was once a gasser.

My '93 Passat AAZ had the same setup.  From what I could gather it only came in that configuration for 1/2 a year.

[Vincent Waldon]

Sounds about right...lots of engineering changes in the early Passats it would seem.

[1outof5]

big daddy did you get my email about the gauge cluster ?

[Big Daddy Roth]

It actuates the diverter flap on the heater box inside the cab.... "fresh air" vs. "recirculate" I believe.

"normal" vs "max air" ?

[Vincent Waldon]

It actuates the diverter flap on the heater box inside the cab.... "fresh air" vs. "recirculate" I believe.

"normal" vs "max air" ?

That sounds more like it.

[Big Daddy Roth]

Ok.

One of the vacuum solenoids on the left inner fender is for fresh or re-circ air. I found a diagram in my benltey for that.

I'm not convinced that vacuum servo on the injector pump is for fast idle. My guess is it's for boost enrichment. I don't see any other reason why there is a limit switch on my throttle.