I've been looking for info on the AAR and most of the discussions have been about the AAR being stuck closed. I'm wondering if mine is letting too much air through at start up? I've got my 1.7L d-jet pretty close to where I want it. When it's warm I'm idling around 900ish. Vacuum lines are new and fuel pressure is perfect.

When the engine is cold and I start it up, it jumps to 2000 to 2300 rpm. When I take the hose off the AAR it's sucking a LOT of air. Restricting it with my thumb of course drops the idle. After about 3 minutes the valve is closing and the idle drops on it's own. There's also a little white smoke at start up.

What do the experts think?

I am no expert but it sounds like it is doing what it is supposed to.

Are you concerned with the speed of the fast-idle?

Shouldn't it start to idle around 1500 to 1800?

Your close enough! It depends on where the mixture knob is at on the ECU, and how far your air bleed screw is at on the TB, and timing. If it's running good, leave it alone.. Your fast idle speed is fine.

I don't know your idle spec.

I can tell you this, the white smoke is not related. Wait until the idle drops and then put your finger over the hole. If the idle drops further it isn't closing completely. I suspect if your idle is wrong you need to set if but that doesn't involve the
AAR.

I see the Cap'n is reading this thread. HE IS AN EXPERT. If he posts, ignore mine.

that's a bit high on the cold idle, but nothing critical. You might have a vacuum leak that doesn't seal until the engine is warm and metal expands.

I've been doing a lot of research into the AAR recently. Agree with the others, yours sounds fine. Leave it alone!

I've got an ad on WTB that's still active - anyone with an NOS 1.7/2.0 AAR that they want to sell, send me a PM.

You could experiment with a plug in the airline with a center hole. That should allow less air in and give you not so high of an idle on start. Maybe a rubber stopper in the airbox port from the inside?