Is an AAR even necessary

[John 9:14]

Is an Auxiliary Air Regulator even necassary in warm weather climates. Mine went bad on my '73 1.7 and I just got off the phone with a Jerry at Pelican and he said in a warm weather climate (Orlando) I can basically remove it, and cap off the lines running to it and it shouldnt be a problem. Any suggestions? Porsche wants 450$ for one and that aint gonna happen.

[bowlsby]

Fuhgeddaboudit.

[Jared at Pelican Parts]

It's actually Jared, and yes, you dont need it. Should make no difference in driveability if you plug the lines up.

[norustscott]

Sounds right to me. It would only be required if you need the cold start injector, hmmmmm come to think of it you really don't need it then...You would just puke a bunch of fuel during warm up. keep in mind that the excess fuel will delute the oil on the cylinder walls during warm up... cuasing some accelerated wear...

[Jared at Pelican Parts]

Just unplug the cold start injector at thesame time

[Will98D]

Cold start injector only works at low temps (below 40F?), so you won't have an excessively rich mixture from that. However, the computer will enrichen the mixture due to a cold cylinder head temp sensor, and it may get too rich without the extra air from the AAR. I have a 1.8 L-Jet, and when the AR wasn't working right the car would start but then begin to load up, and it also will run really slow until it gets to temp. BTW: you can probably get a functional AAR in the parts section of the board for cheap.

[Jared at Pelican Parts]

I drove my 1.7 for 4 years without an AAR, NO problems.

[John 9:14]

Im gonna do as you suggested Jared and begin by replacing all the vacuum lines first. Its getting a little frustrating just trying to get this thing to idle right and start consistently. We put new plugs and points, adjusted the timing. When we began it was just idling to high and sometimes wouldnt start when the engine was warm. Now it idles to low at about 500 when its cold then when it warms up it idles at about 1200 and still wont start sometimes when its warm. Cold it fires right up. I dont know. I just have to go through one thing at a time and eliminate all the possibilities. oh and sorry about calling you Jerry. Thanks for the help.

[Jared at Pelican Parts]

Head temp sensor may be bad as well

[Dave at Pelican Parts]

The AAR will not change the mixture--that is not its function. Its function is purely to give you a higher idle when cold than you would otherwise have. It has nothing to do with the mixture at all.

I would keep the AAR if I could. Otherwise you are going to have to keep your foot on the gas for the first few minutes the car is running in the AM. Even in a warm climate.

If you have a non-functioning AAR, it can very probably be repaired. Take it off the car and hose the inlet and outlet with PB Blaster or Aero Kroyl. Let it sit overnight. Then hook up +12V to the wire on the bottom and ground the case. The bottom of the case should get warm and the valve may close.

If that doesn't happen, you can un-fold the lip of the case that is folded down over the "lid". Then you can pull the lid and the valve mechanism out. Grab the lid with one hand and use a screwdriver to turn the rotary valve. That should free it up.

Make sure that there are 13 ohms resistance between the end of the plug and the case of the AAR. If there are significantly less, then either the wire going into the AAR has worn through its insulation and shorted to the case, or the "resistance wire" has shorted to the case. If there is infinite resistance, then the resistance wire has broken. You can replace the wire with ~13 ohms worth of 1-watt resistors. Hook up one end to the wire coming in through the case, hook the other end to the case. Make sure the connections between the resistors don't touch anything (shrink tubing or tape will work) and make sure that they don't interfere with the valve or the bimetal spring.

The resistors will heat up "about" the same amount as the original resistance wire does. That should close the AAR, if the valve is not frozen.

When you're done messing with the internals of the AAR, you can put it back together again and fold the lip over the lid in a few places. You don't have to make it air-tight.


Uhhh.... This is all in reference to the 1.7 and 2.0 AAR. The 1.8 is somewhat different and I'm not sure how you'd repair that.

--DD

[Va914]

One added not one the AAR assembly....make sure you make note of how the mounting tabs and the hose connections are aligned...

If you don't you will have a hard time getting the hoses connected and oil dip stick out..Don't ask how I know

Cheers
Kerry

[norustscott]

I disagree. True, it does not have any direct mixture control function, it simply allows for a faster idle at start up regardless of the ambiant temperature. The 12v power supply to the AAR coil and the radiant heat from the engine case cause it to close at a variable rate depending on the ambient air temperature. I figure it has to reach about 130 or degrees F, or better, before it closes and shuts off air. This is hot enough to always start "open" in North America. However, It does affect mixure ... If it is cold enough to require the cold start injector to fire, and you do not have the additional air from the AAR to bump the RPM, you are going to have a "richer" mixture during the warm up. Albeit not detrimental if the engine is properly tuned and has the correct FI components.

[M. Hendrix]

The point of the aar is to slow the engine from wearing itself out due to low oil pressure, and contracted metal by idling it high enough to pump oil to the nether regions of your combusters!



AAR is a good thing, whether or not you think you really need it... which you really do, even if you don't, or at least think so.

Just being as clear as possible.



M

[Toast]

Oh yea, got it. Makes complete sense M. Thanks.

[norustscott]

The way I figure it, if it was not needed...as designed, a team of accountants would have loved to omit it from the balance sheet!

[AaronM]

One of the things I have learned about the FI on my 'teener is that it is almost always easier and less stressful to have all the bits a pieces installed than to try to mess with a work around. Which reminds me, I still need to find a thermostat, thermostat mount, and thermostat cable

Aaron

[Kenny Powell]

[QUOTE]Originally posted by Dave at Pelican Parts


I would keep the AAR if I could. Otherwise you are going to have to keep your foot on the gas for the first few minutes the car is running in the AM. Even in a warm climate.

May have to Goose it even Longer! that was enough reason for me!

[Will98D]

Dave - a non-op AAR will result in a richer mixture for the reasons I gave and Scott supported. A low CHT will make the mixture quite rich, and the lack of air from the AAR will make it more so. Same amt of gas + less air = more rich.

The benefit for pumping more oil seems sound, as does not having to dink with the throttle or have it stall when you stop for a light, etc., until it's completely warmed up. I've had plenty of cars you have to piss around with while they were warming up, but for a little time to repair or money to buy used, why bother?

As far as not having to make the AAR "air tight" when you put it back together, I'm pretty sure a leak on the manifold side of the valve would be a bad thing.

[M. Hendrix]

The cold start injector only triggers in -start-.

The supplementary air supplied by the AAR also increases the amount of fuel injected, just as if the throttle were opened by depressing the gas pedal.

Explain the other part of the failure mode that ties the AAR to the CHT again please?

Rich idle can't be *caused* by an AAR.


M

[sean_V8_914]

AAR.....fix it. open the pinch seam, clean it up inside , JB weld it back together, one hour max labor