Two different idles- {Aux Air Valve}

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CBradio
Posts: 283
Joined: Fri Apr 06, 2012 12:03 am
Location: Brooklyn

Two different idles- {Aux Air Valve}

Post by CBradio »

My car idles at about 1000 when i just start it up.

Once it warms, if I shut the car and restart idle climbs to about 1500 or higher

I have replaced lots of things; I have not replaced my aux air valve or thermotime switch.

Based on what Ive read, it seems my 'jules verne' aux air valve is sticking.

Does this seem right?
If so, might i need a replacement or will some wd40 do the trick with this device generally speaking?

What is the best thing to spray in there?

{EDIT} ALSO, if I want to cap the aux air valve tubes and update to the electronic controlled type, where does the input to this electronic valve come from?
Last edited by CBradio on Wed Nov 13, 2013 5:10 pm, edited 1 time in total.
1977 530ia
CBradio
Posts: 283
Joined: Fri Apr 06, 2012 12:03 am
Location: Brooklyn

Post by CBradio »

For those interested, I have confirmed it is my aux air valve stuck in an open position that is giving me a high idle after warm up.......

After warm up, when I disconnect the vacuum tubes from the device and cover with duct tape, my idle drops from 2000 to 1000!

Spraying a bunch of WD40 in there yesterday made no difference.

I would like to upgrade to the electronic type because the 'jules verne' type is so expensive!!

If anybody has any knowledge on the following, it would be appreciated:

1. where does the signal come from for the new style valve?
According to my wiring diagram there is a ground, and there is also a black wire that falls off the wiring diagram I have. Is this just a switched positive?

2. Can I mount it elswhere than the valve cover?

3. as far as the old style goes, any surefire tricks to get it to work again?
I've read elsewhere that "pinching" the bulb that goes into the coolant might help.
1977 530ia
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Mike W.
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Post by Mike W. »

You can mount it where ever you like, as long as the right hoses are connected. It is just switched power, nothing fancy about it. The wires come from a harness you don't have on your car so you would have to get creative. I've never had problems with the older water type, but WD40 is not a good lubricant or penetrant. Liquid wrench or PB Blaster for a penetrant and Triflow for a light spray lubricant.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
T.Hanson
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Post by T.Hanson »

For an extra 2 cents, my '79 with a Nemo starts fine, idles at 1200. As it warms up the idle zooms, hits the limiter, repeats until up to operating temperature. No more problems. Idles at 1200 until shut off.

Procrastination relies on ignoring the zooming, that only happens at stop signs, situations requiring depressing the clutch, idling. Otherwise, motoring along in any gear reaches normal operating temps, zoom free.

Besides the pain in the hassle of disconnecting the (buried) hoses, finding the tube ends rusted, crunchy, pulling the teeny clip off the sensor and not losing it, squirting the innards with penetrating oil as per Mike W's advice, you can put the contraption in the freezer.

Take it out, hold it in your toasty hand and see the piston changing position, IF it's clean and happy back doing its thing, to re-install.
CBradio
Posts: 283
Joined: Fri Apr 06, 2012 12:03 am
Location: Brooklyn

Post by CBradio »

Thanks for the response guys.

Today I:

Dropped the coolant,
took off the old-style valve {some coolant fell out of the chamber where the valve sits, even though I drained.....
I should have pinched some tubes I guess}

I put the "bulb" end in a half-filled cup of boiling water from an electric kettle.

The valve was open 3/4 of the way, i.e. stuck open.

I cleaned the inside as best as I could with some PB blaster,
I even was able to move the inside slide piece slightly with a flathead screwdriver.

I let it sit and repeat the process of a fresh-half-cup of boiling water followed by cold water from the sink applied to the bulb, not the inside of the valve.

It started to open after the PB kicked in.
I did this a few more times, and then I did the same with rubbing alchohol, and lastly, I doused it in tri-flow and opened/closed a few times more. Last it went into the freezer.

I put the valve back on, I put the coolant back in {through a coffee filter} And now my car seems to be holding a steady idle and not climibing like before.
So Thank you Mike, it worked!!

Here are some interesting pictures of a very similar valve deconstructed, there seems to be some wax or something in the bulb:
http://www.benzworld.org/forums/r-c107- ... ucted.html

Also I read here: http://www.topklasse.net.au/forums/show ... php?t=3229
that pinching the bulb is good way to "recalibrate" so it closes all the way.. mine was almost closed all the way but not quiet, so I gave the bulb a little thwack and it was closing all the way. There are also some good pics on that site.
Not sure the 'pinching' was necessary really...but did not feel like dealing with the coolant again!

Thanks again!
1977 530ia
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Jeff Dennis
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Location: Huntsville, Alabama

Post by Jeff Dennis »

I converted the one on my Alfa GTV6 to a manual valve like a manual choke posted it here long ago.
Hanging out in Huntsville
1977 530i 60K
1980 525 Euro
1989 E30 Cab
1992 E30 Cab
1976 R75/6
1974 2002
Alfas
LandShark
Posts: 10
Joined: Thu Jan 09, 2014 3:49 am
Location: ABQ NM

use a heater valve

Post by LandShark »

everyone from alfa to jaguar owners hate the old bosch aux valve

I fitted a heater control valve from a 90's honda civic with associated heater hose. It fits well, controls air manually. Now I just need to run a cable through the firewall for cockpit control. pics coming soon...
76' 633 CSi
LandShark
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Joined: Thu Jan 09, 2014 3:49 am
Location: ABQ NM

posted choke system

Post by LandShark »

76' 633 CSi
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