Auxiliary Air Regulator --- Testing and Adjustment

[TomoHawk]

the thermotime switch closes the circuit to the cold start inject for those few seconds, allowing fuel to pray into the intake manifold. the fuel pump is operated by the starter relay systems an fuel pump relay.

Edited August 18, 2012 by TomoHawk

[Wade Nelson]

Here's another website with some good chat about the AAR

http://www.hiperformancestore.com/Ljetronic.htm

Here's the killer paragraph from this website:

Cleaning the AAV almost always seems to fix them. If it doesn't you may try playing with the little adjustment nut on it. It seems that some AAVs close fully, but don't open very far. This is optimum for horsepower but not for starting in near freezing temperatures. Others open a lot giving great cold starting but don't close all the way which robs some horsepower. With the adjustment nut and a lot of patience you can set up your AAV to suit your needs...well, sometimes...maybe. Furthermore if you adjust the AAV you will probably need to re adjust your idle speed. To optimize it for cold starting take a cool AAV that is at least partially open and jam something inside it to keep it from closing. Now loosen the adjustment nut and then force the AAV to open up a little more. Now while holding it open tighten the nut. That will bias the AAV toward effective cold starting. @To bias it toward more horsepower you can just loosen the nut on a warm AAV, it should then close fully. At this point tighten the nut. You will gain a little power but cold starting will suffer. If you fiddle with it enough you can get it to open most of the way and close most of the way which is how most of them work from the factory. If you have cleaned it, adjusted it and still can't get it to open and close properly you will have to buy another.

[Zed Head]

The AAR just lets air past the throttle body blade. It has the same effect as cracking the throttle open a little bit (he even says that in his writing). I can't see it affecting HP at all. I read through that page and it's an odd thing to say considering the other information he shares.

[Wade Nelson]

The AAR just lets air past the throttle body blade. It has the same effect as cracking the throttle open a little bit (he even says that in his writing). I can't see it affecting HP at all. ... it's an odd thing to say considering the other information he shares.

I'm gonna agree with you. The air flowing through the AAR is getting metered by the AFM, and the ECM is injecting fuel on the total amount of air, both that passing around the throttle throttle and that passing through the AAR, so all it's doing is providing a second pathway. Unless it's disturbing laminar flow or turbulence or swirl or something beneficial within the intake manifold it's hard to see how it could cost any measurable amount of power. Unless this guy has demonstrated a loss on a dyno, he probably misspoke based on some incorrect assumption.

[Wade Nelson]

FWIW, despite numerous attempts at adjustment, I could get my AAV to close all the way, but NEVER to open all the way. It provides a maximum of 150 rpm difference open vs shut, cold vs hot.

Which is perhaps part of my cold starting problem now that cold weather has arrived.