AAV testing, Manual and electric Options

[malcolm2]

Ok. I have had the AAV off for a couple weeks now. I figured it was time to re-install. Wanted to test it first.

I put it in the freezer. The valve was open before and after.

I got the wife hair dryer out and got it hot enough to NOT hold on to. But the valve stayed open.

I got my drill battery out and jumped it to the connector. Very quickly the valve closed.

I decided to blow threw it. Air did not move quickly thru it, but i could hear the hissing as it came out.

So the question is: is the AAV supposed to close up tight?

[Dave_Darling]

Tight-ish. I think that ideally it would completely close, but having it not completely airtight is probably acceptable.

--DD

[jim_hoyland]

Mine closes in 1 1/2 minutes when connected to 12 volts. It's not a solid seal when closed, you can blow air through it. Give it shot of WD 40 before reinstall.

[pbanders]

If it closes when you apply +12V it's working for the most part. It should close when heated externally. My guess is that you're not getting it hot enough with the hair dryer, despite it being too hot to hold. To be honest with you, I've never tested an AAR with just externally applied heat, it could be that it takes a LOT of heat. If it doesn't seem to close all the way, like most old AAR's, it's probably full of gunk. Do as Jim suggests and use some WD40 on it. What I do is let it open fully, then plug one end and fill it about 3/4 with WD40. Plug the other end and shake it like hell for a couple minutes, then dump the WD40 out onto a paper towel. Lots of gunk? Repeat until the stuff that comes out looks uncontaminated. Close it with +12V and check to see if it shuts fully, and watch through the port to see if it closes smoothly. Repeat the overall process until you're satisfied with it's operation. BTW, be extremely careful with the coil wire on the bottom, it's very easy to damage or break, and a bitch to fix.

[timothy_nd28]

The aux air valve should fully close or at the very least close to a tiny leak consistently every time. If this tiny leak is consistent every time, you can tune the idle.
If the AAV happens to close fully one time but closes to a pin hole the next time, you will have a very erratic idle.

Using a hair drier as a test will prove nothing unless you are making a excel graph on closing times in relation to different temperatures (be sure to label the units clearly this time (IMG:style_emoticons/default/biggrin.gif) ). Outdoor ambient air temperature will never cause the AAV to fully close. The dual relay supplies +12 volts as soon as your engine is running, while the ECU supplies the ground. With that said, the AAV is closing immediately when the engine first starts. The case temperature of the AAV will determine just how fast it will close. On a cold day, it will take a little longer for the AAV to close versus a hot summer day. This is what you want, as you don't need a fast idle for very long on a hot summer day.

This AAV is not a special part only used on our 914's. They are used in a ton of different cars, google 1995 infiniti idle air control valve. This is very similar to what we use, perhaps its a better design? Our car is extremely finicky to vacuum leaks, and I have found in the past that the AAV was a source of a vacuum leak thru the electrical connector. You can try cleaning the insides or even try adjusting, but this seems to be a very common part, why not just buy it new?

[malcolm2]

Yes, my 85 VW cabriolet has one.

So maybe the "hissing" is coming thru the electrical connection.... I can try to check that.

1995 would be newer than 1975 (IMG:style_emoticons/default/beerchug.gif) And it is only $55.



But the electrical connector has a "tang" that is different.

[timothy_nd28]

[malcolm2]

So the BROWN piece is my FI harness (AAV connection) and the blue accepts the AAV plug on one end (male) and the Infiniti AAV on the other (female)?

Am I seeing that right?

Or would I need to add this to my harness?

[TheCabinetmaker]

Timothy, do you know of an aav that will provide more air than the djet aar?

[pete000]

I found with the 12 heating the AAR it takes around 3 minutes to close up. Air does bleed by the valve and it is not a total block. I also found out mine would not close until the engine got up to full operating temperature (Hot) this would then close the valve. Turned out my AAR is not receiving voltage from the connector. Any one know where the wires go ?

They disappear into the harness. I think I read the negative is switched from the ECU?

As a quick fix I was thinking about just hooking up 12 volts from the switched position of the ignition to supply power to the AAR.


*Also I found soaking them in Kerosene for a day will free them up.

[timothy_nd28]

Hey Curt, no I don't off hand. But, you could run 2 AAV's in parallel for a Frankenstein setup.

[pbanders]

I found with the 12 heating the AAR it takes around 3 minutes to close up. Air does bleed by the valve and it is not a total block. I also found out mine would not close until the engine got up to full operating temperature (Hot) this would then close the valve. Turned out my AAR is not receiving voltage from the connector. Any one know where the wires go ?

They disappear into the harness. I think I read the negative is switched from the ECU?

As a quick fix I was thinking about just hooking up 12 volts from the switched position of the ignition to supply power to the AAR.


*Also I found soaking them in Kerosene for a day will free them up.

The ECU has nothing to do with the +12V to the AAR, voltage is supplied from the relay plate after the key is turned on, and stays on until the key is turned to off. Negative is not switched, it's provided by the case, there's only one wire connected to the AAR. The wiring diagrams for the AAR and the relay plate are available on the Pelican Parts web site.

[malcolm2]

All the pix above show 2 connectors on the AAV. And my harness with the black connector has 2 females.

[malcolm2]

I also checked Pin 88d of the dual relay to one pin of that connector and it showed continuity.

The other pin on the AAV connector showed continuity to ECU pin 34.

[malcolm2]

My prosperos garage diagram has the AIR VALVE with 2 wires. One to ecu, one to dual relay as measured above.

[pbanders]

Crap, this is a 1.8 (L-Jet), I'm thinking it's D-Jet. Ignore all I've said, sorry, I'm too D-Jet centric.

[Rob-O]

Yes, my 85 VW cabriolet has one.

So maybe the "hissing" is coming thru the electrical connection.... I can try to check that.

1995 would be newer than 1975 (IMG:style_emoticons/default/beerchug.gif) And it is only $55.



But the electrical connector has a "tang" that is different.

The tang isn't holding that connector on. Why not just dremel it off the new part?

[pete000]

I will have to check my dual relay pin 88d and the pin 34 on the ECU.

So far I haven't found any continuity between either wire at the AAR.

Great thread !

Found this on the dual relay...

http://www.thesamba.com/vw/forum/viewtopic.php?t=334340

[malcolm2]

The tang isn't holding that connector on. Why not just dremel it off the new part?

The tang is for orientation. It would certainly work with out the tang. I suppose great care would be needed to keep the connections straight everytime you connect it. I don't want to be called a DAPO in 20 years when some newbie buys my car. (IMG:style_emoticons/default/WTF.gif)

As much as i like the square aav, i like my harness more. I really don't want to hack it up. I have at least two maybe 3 other aav from other cars and spare engines lying around. I think i will pull them out and compare operation and how well they seal.

[malcolm2]

Crap, this is a 1.8 (L-Jet), I'm thinking it's D-Jet. Ignore all I've said, sorry, I'm too D-Jet centric.

Thanks for chiming in anyway. (IMG:style_emoticons/default/lol-2.gif)