Author Topic: What is this?  (Read 1872 times)

January 29, 2010, 12:16:32 pm

dokarex

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What is this?
« on: January 29, 2010, 12:16:32 pm »
http://www.vwcaddyforum.com/showthread.php?t=33647
In the picture of the AAZ pump(scroll down) what is the round black thing coming out of the LDA. With vacume applied to it does it keep the LDA diaphram from moving,to improve emissions? I believe it was once hooked up to a micro switch tha once certain rpms we obtained it closed the switch cutting ff the vacume and let the LDA work? Should I remove the vacume line so it will work?
If I'm wrong let me know.
Sorry about the link but it was all I could find for a pic of this part.
« Last Edit: January 29, 2010, 12:37:13 pm by dokarex »


1987 1.9TD Doka from Germany gasser DU tranny, fuel turned up, 1.6 LDA pin, boost at 15 psi,egt and boost gauges,stock diesel tach,air filter behind passenger tail light, IC to come
2005 Jetta Wagen TDI
B6200 Kubota Diesel
16ft Freestyle catermeran
16ft Sunray 85HP

Reply #1January 29, 2010, 12:38:52 pm

blackdogvan

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Re: What is this?
« Reply #1 on: January 29, 2010, 12:38:52 pm »
High idle vac actuator. Its run from a vac valve that uses the same temp switch as the GP cutoff. Mine works great, GP's stay on for a few seconds & then when there is enough vac the idle kicks up 200rpm. Once the engine comes up to temp it settles down. The 2.4 IDI's i've seen in the eurovans had a version that used coolent only to actuate the high idle instead of my AAZ version thats more complicated IMO.
1991 Vanagon 1.9 mTDI

Reply #2January 29, 2010, 01:00:34 pm

dokarex

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Re: What is this?
« Reply #2 on: January 29, 2010, 01:00:34 pm »
Since I transplanted the aaz into a Doka, I've stripped all the electonics of this means the high idle actuator always has vacume going to it. Should, once the engine is warmed up, this shut off so it will idle properly?
1987 1.9TD Doka from Germany gasser DU tranny, fuel turned up, 1.6 LDA pin, boost at 15 psi,egt and boost gauges,stock diesel tach,air filter behind passenger tail light, IC to come
2005 Jetta Wagen TDI
B6200 Kubota Diesel
16ft Freestyle catermeran
16ft Sunray 85HP

Reply #3January 29, 2010, 02:09:53 pm

Vincent Waldon

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Re: What is this?
« Reply #3 on: January 29, 2010, 02:09:53 pm »
Since I transplanted the aaz into a Doka, I've stripped all the electonics of this means the high idle actuator always has vacume going to it. Should, once the engine is warmed up, this shut off so it will idle properly?

Sure.

Or simply disconnect it, delete it, and adjust the idle speed as required with the set screw... this is the approach most people use.  The less vacuum hoses and actuators the better??!!

This has been my approach... the only loss is that in its stock config the fast idle is also actuated when the A/C is on... so my car vibrates a bit more at idle when I have the A/C running.  Ah well...   ;)
« Last Edit: January 29, 2010, 02:58:34 pm by Vincent Waldon »
Vince

Edmonton, Alberta, Canada
2001 silver TDI Jetta Malone Stage 1.5 , 2001 blue TDI Jetta SBIII 216s Malone Stage 3, 1970 Bay Window bus

Gone but not forgotten: 1969/1971 Beetles, 1969/1974 Westies, 1979 Rabbit, 1986 TD Jetta, 1992 gas Jetta, 1994 TD Jetta

Reply #4January 29, 2010, 02:24:10 pm

blackdogvan

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Re: What is this?
« Reply #4 on: January 29, 2010, 02:24:10 pm »
If you're deleting the high idle go for the GP relay that keeps them on the longest after start, not sure what the part number is for that tho, sorry. TDI part IIRC...
1991 Vanagon 1.9 mTDI

Reply #5January 29, 2010, 05:36:16 pm

dokarex

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Re: What is this?
« Reply #5 on: January 29, 2010, 05:36:16 pm »
thanks this will clean up the engine quite a bit as there will be no more vacuum lines and one less thing hanging off the ip
If the high idele actuater is siezed from always being under vacuum (except when not running), what cold you use to free it up?
1987 1.9TD Doka from Germany gasser DU tranny, fuel turned up, 1.6 LDA pin, boost at 15 psi,egt and boost gauges,stock diesel tach,air filter behind passenger tail light, IC to come
2005 Jetta Wagen TDI
B6200 Kubota Diesel
16ft Freestyle catermeran
16ft Sunray 85HP