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Discussion Starter #1
My Alfa is running great but it requires me to press the accelerator when starting the car cold. I've fought an aging AAV for the last few years so today I decided to by the valve from Advance Auto to fab up a manual AAV.
Well, there happens to be a 'Pick 'N Pull' on the way to the store so I deided to stop in and check things out. I found a very abused '79 Dautsun 280Z that had a AAV. I pulled the part, not expecting much (I've tried this before). Upon inspection, I found the strip to be opened a fair amount and I could easily move it with my screwdriver.

Well, I figure I've got my basis covered..I'll try the 280Z part and if I don't have luck I'll install the manual arrangement.

I pulled the AAV off my car and compared it with the 280Z part. The part off my car (cold) was not open nearly as far as the 280Z AAV. I tossed them both in the freezer for about 45 minutes and the 280Z part was definately open wider, which should equate to easier cold starts.

From the freezer to the oven at about 175F. Both parts were fully closed.

I installed the 280Z AAV on my car and it started right away without feathering of the gas pedal. The car idled nicely at about 1200 rpm. I took it out for a drive and as the car was reaching operating temperature I came to a stop light and the car was iding at about 1800 rpm! About 5 minutes later at another light the cars idle was still high, but coming down (1400 rpm).

Later the car idled right where it use to, around 900 rpm. I assume the heating element may not be working correctly.

I'm going to leave it on the car for a few days or so just to get a better idea of its characteristics. I do like the car starting right up like it use to years ago.

I know the manual system will work, I just hate having to go that way if I can avoid it. I don't see a great spot to mount the cable in the interior for one thing. My car has power mirrors so the spot Tifosi used is not an option.

We'll see!
 

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I bought a new 81 280zx AAV. It idles high at first and then settles down. But when real cold it went up to 2k when idling. Normal was 1.2 to 1.5k.

Someone said I needed some kind of air restrictor. I found a simple valve/lever from Home Depot. I put it inline with the AVV hose. I had some extra hose when replacing it with the kit from HiPerformance. I started the car on a real cold day and just turned the lever until I got the idle where I wanted it.

I will take pics later when I get a chance.
 

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Someone said I needed some kind of air restrictor. I found a simple valve/lever from Home Depot. I put it inline with the AVV hose.
That sounds like a clever solution. Or perhaps a second piece of hose that fits snugly inside the AAV's hose to restrict air flow? Or a metal sleeve inside the hose - drill a medium size hole and enlarge the hole until you get the desired cold idle speed? As long as the AAV closes when warm then the warm idle should be correct.
 

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I made that comment quick this morning before leaving for work. Eric was the one who gave me the idea. I didn't know how much to restrict or what would fit that would work. That is why I went first with the valve. It looks cool in the engine bay.

I can also adjust it based on the weather. But the end result is the AAV closes once it's warmed up anyway.

My setup allows me to not have to go the manual route. I didn't feel comfortable running a cable through the firewall and having to mount a knob inside.

Again, thanks to Eric for the idea.
 

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Discussion Starter #5
Great ideas! Thank you. I will mess with it this weekend as we are getting into the high 30's tonight in NW Florida!

One thing I noticed though was the in/out diameters of the both AAV's were the same. It's simply that the 280Z AAV opens wider.

Both were fully closed but I didn't pay any attention to how long it took.

This will be fun!
 

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The Japanese version is basically a clone of the Bosch part. As far as I can tell the only difference between the various models is how big the opening is and how quickly they close off the flow.

If it's like the Bosch ones there's a nut that can be used to adjust the size of the opening. If you slightly loosen the nut, the screw it is on can be moved in a slot to widen/shrink the hole.
 

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Discussion Starter #7
Oh yeah...
Was back at Pick N Pull today for another car...Son's BMW had the drivers side mirror (glass) fall out of the mirror this morning as he pulled out of the driveway!

I was close to the Yard when he called so I stopped in and picked up the mirror for $4.25.

Of course, I had to look around. I found an 85 SAAB that had an AAV that looked like a good candidate. I didn't have any tools with me to pull the thing but I think I will on the next visit.

I'm sure not worried about anyone getting be for I do!
 

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Discussion Starter #8
The Japanese version is basically a clone of the Bosch part. As far as I can tell the only difference between the various models is how big the opening is and how quickly they close off the flow.

If it's like the Bosch ones there's a nut that can be used to adjust the size of the opening. If you slightly loosen the nut, the screw it is on can be moved in a slot to widen/shrink the hole.
Yeah, I'm aware of the nut, just never saw it make much difference.
 

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The 280Z AAV is so close it worked fine for me. I originally did the pick-A-Part, like you, and later found a new 280Z AAV on online. I have a post where I cut both open and you can see the difference, which is not much.
 

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Yeah, I'm aware of the nut, just never saw it make much difference.
Me three.

I cut apart an old AAV - pictures here. The amount of bias available by loosening that nut and trying to re-position the vane is small.
 

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Discussion Starter #12
The 280Z AAV is so close it worked fine for me. I originally did the pick-A-Part, like you, and later found a new 280Z AAV on online. I have a post where I cut both open and you can see the difference, which is not much.
I saw your post the other night while searching. Appreciate you having taken the time to cut the thing open. Very helpful.
 

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Discussion Starter #13
Still playing with the AAV stuff. I decided to try a 'restrictor' in the line from the AAV to the intake.

I removed the hose and inserted a section of smaller hose inside. The car didn't cold start as easy. I'm not sure I have any other hose I can use as restrictor that would still fit snug in the original hose. Guess I was just hoping to get lucky and find a restrictor that would still allow easy starts but reduce the idle to an acceptable level, say, 1200 rpm, until warm.

I like the idea of the adjustable valve inline with my AAV but the one from Advance is kind of overkill as far as the size of the valve.
 
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