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bd1308
when the AAR is disconnected and ports plugged, the cold start idle is VERY slow....like a tractor idle or something. I have to bump the idle screw to get it to actually idle.

then it will idle warm at like 1500-1700 RPM...which is way too high.

AAR connected, the engine WONT stay running cold(have to rev to 3000 for 1-2 minutes to hold idle)....when warm, the idle is fine...something like normal.


?

b
ClayPerrine
Does the electrical portion of the AAR work?

The AAR provides the "fast idle" to the engine when its cold. Without it the car will not idle cold.

Inside is a bi-metallic element that moves a window blocking off the hole through the AAR. closed, the engine idles normally. Open it idles fast.

Around the bi-metallic element is an electric heater element that is powered by the ignition circuit.

If the window does not move, the AAR is bad and should be replaced.
r_towle
ok,
diconnect the AAR.
Plug the vacuum ports so you dont get a vacuum leak.

Get the car warm, then set the idle...dont set it cold.

Then re-connect the AAR and see what happens.

All it is doing is adding extra air during warm up...
And its not that much.

I read somewhere that a rabbit aar is the same, so you can get them at a junk yard.

My djet one is not connected..
The ljet will be disconnected when it dies...it really is not needed...just let it warm up,

Rich
bd1308
yeah my last one like broke apart (The electrical part and the mechanical part seperated)...

i'll try and see whats going on.

it SHOULDNT not idle, doesnt make much sense, unless the resistance is way off from the new TS sensor and the head not having much thread left.

b
ClayPerrine
Did you plug the hole in the intake tube before the throttle body?

If not, you have "false air" and that will cause lots of idle problems with an L-jet system. Because the air being used for combustion is not passing the air flow meter, it runs really lean.

Warm the engine up to operating temp. Plug the AAR, and set the idle speed.

This should be the correct warm idle. Any fast idle when cold is controlled by the AAR.
bd1308
I have one that fell apart...stuck closed when i "fixed" it.

and the other one is stuck open i think.....


does anybody have a good working AAR that isnt 400 dollars?

b
John
Pelican has new ones for $225 or so....



Pelican Parts
bd1308
i saw those....thx.

b
r_towle
HELLO

Rabbit, junkyard....

I know its not a 914 only part.

Your a computer guy...hunt for the part number...

Rich
ClayPerrine
Go to the local wrecking yard. Find a Toyota or Nissan from the early 80s. If it doesn't have a carb, it has a licensed copy of the bosch L-Jet system. The AAR from any of those should just bolt in.

bd1308
I have the PET.

I'll look it up, but I have a Q....

does anybody have a working 914 where they could extract a cold-condition Head temp resistance readout?

b
r_towle
QUOTE (ClayPerrine @ Jan 30 2006, 02:13 PM)
Go to the local wrecking yard. Find a Toyota or Nissan from the early 80s. If it doesn't have a carb, it has a licensed copy of the bosch L-Jet system. The AAR from any of those should just bolt in.

agree.gif


or,
vw type 4 1974
vw beetle
vw bus
triumph tr7/8
renault
porsche 928 1980-84
opel manta
vw vanagon 80-83

there is a start...

There are more that are liscensed...but if you have the part number...you can figure it out at the junk yard...

Basically its not a complicated part....it is a thermo switch that opens at a certain temp and closes at a certain temp.

Rich
bd1308
okay lemme ask a Question about my aar...

the end (plastic part) spins around kinda freely....

the plug-in is now vertical and the window is now fully open...is this the way its supposed to be?


b
lapuwali
Yes, the L-Jet AARs are all the same, and L-Jet was used on a zillion cars. You should be able to find junkyard parts very easily. That said, I've rarely seen an L-Jet car that actually had a WORKING AAR.

With ALL of the holes plugged (remember, you have to plug the holes on the plenum AND the other end with L-Jet), with the idle set to a reasonable value HOT, then you should be able to keep it running cold with your foot on the gas.
rhodyguy
is there a bench test to determine if a aar is functional, or only if you put it on the engine. did you try the cold start procedure britt?

k
lapuwali
The AAR is just a bimetal strip controlling an air valve. The electric connections are a heater to make the strip move faster. Cold = open, hot = closed.

To test an AAR, put it in the freezer and wait a while. Take it out, and look through the air holes. You should see daylight. Hook the electrical terminals to ground and +12 (doesn't matter which way), and wait a bit. You shouldn't see daylight now. Put it back in the freezer and wait until it closes again. Take it out and let it heat up on its own, and you should see it at least partially open.

They can stick in position, open, closed, partially open. The bimetal strip that controls it can break, so it will never move. The heater wires can break, so the bimetal strip may make it move strictly from engine heat, but it will take a good long time for it to close completely.

You can also try blowing through it. You shouldn't be able to with it closed completely.

ClayPerrine
Britt, the plastic part on the end should NOT spin. It's broken. Toss it and get another.


AAR testing procedure.

Put it in the freezer. Wait a couple of hours. Look down the hole. The window should be closed.

Put it in the oven and set oven to it's lowest temp. Wait about 30 minutes. Look down the hole. The window should be open.

Check the electrical contacts for continuity. If it is present, put the aar back in the freezer. Wait an hour. Pull it out, and hook the two contacts on the aar to a 12v battery while watching in the hole. The window should open up slowly.


Oh, and make sure to put a fuse in the circuit of the test rig.


rhodyguy
could one just us a bat charger for the test? pm sent britt.

k
ClayPerrine
QUOTE (rhodyguy @ Jan 30 2006, 01:56 PM)
could one just us a bat charger for the test? pm sent britt.

k

Yep.. .the aar electric circuit is nothing more that a heater element. A battery charger will work fine.
rhodyguy
one step further. my old aa catalog shows 2 items. 022 906 045 for the 1.7/2.0 ($295) and 022 906 045 A for the 1.8 ($75), new. other than $220 what's the dif?

k
SLITS
Porsche 022 906 045 = Bosch # 0 280 140 008
VW 022 906 045 = # 0 280 140 008
VW 022 906 045A= # 0 280 140 101
VW 022 906 045A= # 0 280 240 102

Any of these and more................
ClayPerrine
The D-Jet AAR is a metal can with a inlet in the top and another in the side. It only has one wire and grounds through the case. It does exactly the same function as the L-Jet AAR. The L-Jet AAR can be subbed for the D-Jet AAR, but you have to add a ground wire to use it.


bd1308
they look completly different. Other than that they both function just the same. I have two of the 1.7/2.0 ones and both dont work i think....

but I figured out how the 1.8 ones work and I noticed that the plug thing wasnt in the stock position, so I fixed it and I epoxy'd both edges and its setting now....

b
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