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  #1  
Old 11-16-2006, 09:07 PM
rrgrassi's Avatar
mmmmmm Diesel...
 
Join Date: Jun 2006
Location: Royse City Tx
Posts: 4,875
Vacuum Line Issues

Well, while driving home, I went from a tranny that shifted normally to one that shifted abruptly at high RPM. I found a broken vacuum line going to the 3-2 valves on the valve cover.

I followed Brian's aka Brain instuction on nixing the EGR and 3-2 valve assembly. Now here is my problem...the hack job done by the PO's mechanic.

1. There was no vent running to the cabin. That is solved now.
2. Tranny flairs like crazy now, but at least the car shuts off super fast now. I know I will need to turn the tranny modulator back abit, or hook the vent line up elsewhere.
3. The hack job has the vacuum lines in a mess. Below is the current hook up, so I need to know the correct hook up.

From the main line tha goes to the booster, it has two small line connections.

One is hooked up to a 4 way T. The 4 way now has a plugged port since it ran to the 3-2 valves. The 2 remaining ports are as such: One runs to the white 2 port one way valve that has the yellow and the yellow/gray striped lines that runs through the firewall. The other port runs to a 3 way T that goes to the top of the "vacuum sensor" on the IP and the green "dashpot" which then runs to the tranny modulator.

The second port on the mail line goes to a 3 way T that is connected to a blue two port one way valve which are connected to a brown line and a green/yellow stripe line that run through the fire wall.

The vent line was hooked up to the 3-2 valve, and then to the bottom port on the "vacuum sensor". That line is now running to the cabin.

There is also a Brown/Purple stripe running from the firewall the the IP

I need to know just how the lines are supposed to connected. It does not look right to me. The tranny flairing did not begin until I abolished the EGR and 3-2 valve circuit.

I hope the cobbled together diagram helps.


Yellow Yellow/gray
|| __ to top of"Vacuum Sensor"
Plugged-+--__ To "green dashpot" and modulator
|
______________|_____________________Brake Booster
|
Brown-| |-Green/Yellow Stripe
-----Black vent line on bottom of "vacuum sensor" to firewall

Thanks!

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RRGrassi


70's SPM #5608 Fairmont A-4 MOW car

06 VW Jetta TDI 280K miles

03 VW Golf TDI 5 speed 400K Miles Engine died

RIP--Lost in fire...82 300D 322K was My Daily Driver-On the search for a w126 now...

90 Dodge D250 5.9 Cummins/5 speed. 400K
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  #2  
Old 11-17-2006, 12:05 AM
300SDog's Avatar
gimme a low-tech 240D
 
Join Date: Jan 2003
Location: central ky
Posts: 3,602
Here are vacuum line diagrams for the 123: Vacuum Diagrams
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  #3  
Old 11-17-2006, 10:01 AM
rrgrassi's Avatar
mmmmmm Diesel...
 
Join Date: Jun 2006
Location: Royse City Tx
Posts: 4,875
OK, thanks! The diagrams are a huge help!

The green "Dashpot" or correctly called vacuum damper, appears to be in the wrong spot according to the diagram.

It also looks like I have some missing vacuum orifices as well. Problem is, I do not know which ones are missing.

I did notice much better performance by nixing the EGR vacuum circuit.
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RRGrassi


70's SPM #5608 Fairmont A-4 MOW car

06 VW Jetta TDI 280K miles

03 VW Golf TDI 5 speed 400K Miles Engine died

RIP--Lost in fire...82 300D 322K was My Daily Driver-On the search for a w126 now...

90 Dodge D250 5.9 Cummins/5 speed. 400K
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  #4  
Old 11-17-2006, 10:32 AM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396


This is your vacuum diagram.

It can flare for one of two reasons:

1) Item 63 is missing. It is imperative that this restrictor be present otherwise the trans will see too much vacuum.

2) The adjustment of item 65, the vacuum control valve, is incorrect. Disconnect the line to the vacuum control valve and connect the Mityvac. Pump up the Mityvac and see what you get at idle (engine not running).

Then, open the rack and watch the Mityvac. The gauge should fall gradually toward zero. If it remains at high vacuum, the VCV is the culprit.

If the modulator is leaking slightly, you'll have to continually pump up the Mityvac to the leak point........be careful with obtaining data under this condition.

You may wish to connect the Mityvac directly to the transmission line, first, and pump it up. See if it holds vacuum before continuing with the aforementioned test.

Last edited by Brian Carlton; 11-17-2006 at 10:37 AM.
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  #5  
Old 11-17-2006, 11:23 AM
rrgrassi's Avatar
mmmmmm Diesel...
 
Join Date: Jun 2006
Location: Royse City Tx
Posts: 4,875
Brian, thanks for the additional info!

Anyone know what color, part number, and where to get item #63?

Thanks!
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RRGrassi


70's SPM #5608 Fairmont A-4 MOW car

06 VW Jetta TDI 280K miles

03 VW Golf TDI 5 speed 400K Miles Engine died

RIP--Lost in fire...82 300D 322K was My Daily Driver-On the search for a w126 now...

90 Dodge D250 5.9 Cummins/5 speed. 400K
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  #6  
Old 11-17-2006, 01:09 PM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396
Quote:
Originally Posted by rrgrassi View Post
Brian, thanks for the additional info!

Anyone know what color, part number, and where to get item #63?

Thanks!
Well, it's definitely a dealer item. Sam Ross posted some p/n's, but, I think that they might be erroneous based upon another members's attempt to purchase same.
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  #7  
Old 11-17-2006, 01:52 PM
rrgrassi's Avatar
mmmmmm Diesel...
 
Join Date: Jun 2006
Location: Royse City Tx
Posts: 4,875
Ok, thanks again Brian. It would have been really helpful if the diagram gave a part number, or a color to ID it rather than just "orifice".

Oh well. I can at least test to see if the modulator is leaking.

Now, I just gotta find the #63!
__________________
RRGrassi


70's SPM #5608 Fairmont A-4 MOW car

06 VW Jetta TDI 280K miles

03 VW Golf TDI 5 speed 400K Miles Engine died

RIP--Lost in fire...82 300D 322K was My Daily Driver-On the search for a w126 now...

90 Dodge D250 5.9 Cummins/5 speed. 400K
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  #8  
Old 11-17-2006, 02:04 PM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396
Quote:
Originally Posted by rrgrassi View Post
Ok, thanks again Brian. It would have been really helpful if the diagram gave a part number, or a color to ID it rather than just "orifice".

Oh well. I can at least test to see if the modulator is leaking.

Now, I just gotta find the #63!
Look around carefully under the hood. If it's inline, you'll see a very thin piece of plastic between two hoses. It's easy to miss.
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  #9  
Old 11-17-2006, 02:13 PM
rrgrassi's Avatar
mmmmmm Diesel...
 
Join Date: Jun 2006
Location: Royse City Tx
Posts: 4,875
Quote:
Originally Posted by Brian Carlton View Post
Look around carefully under the hood. If it's inline, you'll see a very thin piece of plastic between two hoses. It's easy to miss.
I have looked. Spent time last night, and today at lunch. Some idiot hack left no orifices. Some of the things I am finding can be the poster children on what not to do.
__________________
RRGrassi


70's SPM #5608 Fairmont A-4 MOW car

06 VW Jetta TDI 280K miles

03 VW Golf TDI 5 speed 400K Miles Engine died

RIP--Lost in fire...82 300D 322K was My Daily Driver-On the search for a w126 now...

90 Dodge D250 5.9 Cummins/5 speed. 400K
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  #10  
Old 11-17-2006, 06:19 PM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396
Quote:
Originally Posted by rrgrassi View Post
I have looked. Spent time last night, and today at lunch. Some idiot hack left no orifices. Some of the things I am finding can be the poster children on what not to do.
Well, it's then going to be a struggle with the dealer.........in a vailant attempt to find a part number.

Alternately, I bet that one of the members can hook you up with one from parts car.

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