Tandem pump question

Dimitri16V

Top Post Dawg
Joined
Jan 30, 2005
Location
DE
TDI
01 Golf, 04 Golf
is the vacuum outlet supposed to spin freely ?
I experience sporadic loss of power brakes and everything else checks OK
 

Jettascuba

Veteran Member
Joined
May 27, 2009
Location
South Africa
TDI
2002 VW Jetta
Yes, it is supposed to 'spin' freely. Check the connection just aft of the vacuum pump - in fact check all the connections. These pipes do tend to crack at the connections. If you wonder about the vacuum pump, remove the vacuum line at the y-connection just beyond the intake manifold and feel, listen for vacuum while the engine is running. This is the line that is also plumbed into the brake vacuum line.
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
12' RAM 2500 QC,LB. 2019 Cherokee 2.0T
With 205K it wouldn't surprise me if it were going out. I'd replace it, the next bit to fail will be the shaft seal and that'll flood the engine with pressurized diesel.
 

Dimitri16V

Top Post Dawg
Joined
Jan 30, 2005
Location
DE
TDI
01 Golf, 04 Golf
Actually 351K miles
i will run some vacuum tests in the weekend
 

Mako

Veteran Member
Joined
Apr 4, 2011
Location
Cape Town
TDI
AMFPolo 1.4 TDI 100%Biodiesel, AHF Golf TDI 100% Biodiesel, AHF Golf TDI Wagon 100% Biodiesel, VW Syncro 3CT Kombi 100% Biodiesel, Corsa 1.7D 100% Biodiesel
Vacuum spigot connection should not spin freely and will loose vacuum. Easily repaired with epoxy.
 

Dimitri16V

Top Post Dawg
Joined
Jan 30, 2005
Location
DE
TDI
01 Golf, 04 Golf
Vacuum spigot connection should not spin freely and will loose vacuum. Easily repaired with epoxy.
you are correct

Perfect timing I read this , just got done troubleshooting it
I put a vacuum gauge , pumped the brake booster down thru the hose with the one way valve , vacuum was leaking slowly . Discovered hose has a crack in the bend
put some tape to seal it , hooked up a vacuum gauge on the T in that hose , pumped the booster down , vacuum holds

reconnected everything . started the car , vacuum built up slowly to -1000 mbar. Tandem pump outlet is wobbly , moving around makes vacuum drops to -500mbar

also noticed oil in the vacuum outlet .lately I had excessive oil consumption , I think the vacuum pump has been sucking air thru the wobbly outlet and pressurizing the crank case sending more oil thru the PCV

now who has the best prices for a tandem pump and booster vacuum hose ? the epoxy might work but at 350K miles , I am sure the fuel part of the pump has to have some wear
 
Last edited:

Fasteddie10

Veteran Member
Joined
Jun 23, 2011
Location
Illinois
TDI
2004 Jetta Wagon TDI, 2-2005 Passat Wagon TDIs, 2-2004 Passat Wagon TDIs
Tandem Pump

My 2004 Passat had intermittent issues with the turbo boost. I found the vacuum supply varying from 19 inHg Vac to 10 inHg Vac. Found the tandem pump nipple loose and wobbly. This pump is the LUK and the nipple looks like it was pressed in and I did not see a way to fix it other than glue. My 2005 Passat has the Bosch pump, the nipple is screwed in on this pump, you can see the hex head on the nipple base. The output of the 2005 pump is 25 inHg Vac and steady.

So found a new Bosch Tandem pump on eBay for $250. This pump puts out the 25 inHg Vac. Works great now!
 

drehenkraft

Member
Joined
Apr 28, 2006
Location
Tempe, AZ
TDI
2005 Passat TDI GLS Stonehenge Grey/Grey
...
now who has the best prices for a tandem pump and booster vacuum hose ? the epoxy might work but at 350K miles , I am sure the fuel part of the pump has to have some wear
metalmanparts.com $290 shipped. Just got mine, debating self-install vs my local indy shop.
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
12' RAM 2500 QC,LB. 2019 Cherokee 2.0T
Passat is a PITA due to tight confines. You can do it though with some patience.
 
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