Beware of the Plenum Leak!

tiri.liri

Active member
Joined
Jul 17, 2009
Location
Canada
TDI
2005 Passat GLS TDI Sedan
I am interested in 2 "doses"... But what are the options about shipping to Canada?
(I hope the shipping is not 30+$):confused:
 

deming

Veteran Member
Joined
Nov 9, 2003
Location
Illinois
TDI
(2) 2005 TDI Passat Wagons
Job Completed on Plenum water leak

I just wanted to thank everyone for all of the assistance, photos and guidance on this update and repair.

Battery and wipers were removed. Battery terminal puller worked great!

The (2) rubber body plugs in the bulk head were removed.
1 under battery and 1 under brake booster. I think I removed all problematic body plugs.
I cleaned all of the dirt and crap out of the bulk head area.

Pulled out the plenum / Hepa filter housing and re-sealed using the VW approved OEM cording material.
Snipped / opened up the sunroof drain vent tubes on both front doors as well.

It takes 2.0-3.0 hours and that is taking your time and being meticulous.

Thanks again TDI club !!

Do you guys think this plenum will need to be cleaned and re-sealed again in a few years ?
 
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aja8888

Top Post Dawg
Joined
Dec 25, 2007
Location
Texas..RETIRED 12/31/17
TDI
Out of TDI's
I'd be more concerned about keeping the plenum drain holes open and not having water pool up before I'd go after the seal again. But for a few bucks and an hour, it may be worth checking it in a couple of years.
 

Turbospool

Veteran Member
Joined
Sep 15, 2007
Location
Daleville Va
TDI
2001 White TDI Jetta, 280k, 2003 jetta 270k
found this thread after I did a search ..... I suppose I'm in for big bucks :( I found 1 & 1/2 inches water in the pass side back foot well ..... my car suddenly is not shifting proper and got a engine check light on :mad: . It seems I'm in serious trouble here .. learning this all too late. Wonder what you guys would advise from this stage of the game??/
bummed in Va.
 

eyeguy

Veteran Member
Joined
Sep 3, 2005
Location
Charleston, WV
TDI
'05 Passat Wagon TDI
I bought the seal material today to hopefully fix the issue. Luckily, I have plastic formed floor mats & noticed a little pool of water. Opened the glove box & found some wet papers there as well. I ended up buying a 10 meter roll since the dealer didn't know how to order less, so I figure the wagon is good to go for the next 100+ years or so!
 

1854sailor

Resident Curmudgeon
Joined
Aug 10, 2004
Location
Westerly, RI
TDI
2015 Golf SE SportWagen, 2015 Golf SE Hatch Back.
found this thread after I did a search ..... I suppose I'm in for big bucks :( I found 1 & 1/2 inches water in the pass side back foot well ..... my car suddenly is not shifting proper and got a engine check light on :mad: . It seems I'm in serious trouble here .. learning this all too late. Wonder what you guys would advise from this stage of the game??/
bummed in Va.
Do a search of this forum. Thundershorts rescued a Passat that had been underwater. He opened up the TCM and ran it through a dishwasher cycle, which cleaned and dried it. It worked for him.
 

thundershorts

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Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
that is true, the sooner you open it up and clean it the better. Mine probably was wet for two months. sprays don't work very well as the salts are not soluble in petrochemicals but are in water and alcohol. water from being submerged activates the acid based flux and ends up crusting with lead/tin salts. Btw, my ccm actually worked filled with water. It is important to completely dry harness and connectors as well...really dry, meaning removal of carpet.
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
Its also advisable to open up the tcm harness a foot or so from the tcm plug and address the crummy ground splice. A good opportunity to put star washers and no-alox on the ground studs as well. Its been two years since my car was a submarine and everything works.
 

kjclow

Top Post Dawg
Joined
Apr 26, 2003
Location
Charlotte, NC
TDI
2010 JSW TDI silver and black. 2017 Ram Ecodiesel dark red with brown and beige interior.
If the carpet and mat got wet, then you'll have to pull the seats, trim, and get the carpet and mat away from the floor boards. I was amazed at how much water the padding held when my daughter left the driver's window down. I ran the blower from the shop vac under the pad for about 18 hours and it was still slightly damp when I put it all back together.
 

Turbospool

Veteran Member
Joined
Sep 15, 2007
Location
Daleville Va
TDI
2001 White TDI Jetta, 280k, 2003 jetta 270k
If the carpet and mat got wet, then you'll have to pull the seats, trim, and get the carpet and mat away from the floor boards. I was amazed at how much water the padding held when my daughter left the driver's window down. I ran the blower from the shop vac under the pad for about 18 hours and it was still slightly damp when I put it all back together.
Thanks.... gonna go after it and see if Thundershorts idea of drying the works might work. Also, is the gasket under the air filter the sole culprit for the initial leak here? Thanks.
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
your leak most likely was caused by the two drains in the plenum being plugged, under battery and brake booster, not by seal failure.
 

Turbospool

Veteran Member
Joined
Sep 15, 2007
Location
Daleville Va
TDI
2001 White TDI Jetta, 280k, 2003 jetta 270k
What car are you talking about?
2004 tdi passat..... and I pulled the tcm , found it all wet... wiring wet... so I washed it in dishwasher to clean it. Dried it and will be installing soon to see if she will run. The drain holes were open in the plenem .. it appears the cowl that covers around the wipers was loose from windshield and may have been the culprit, letting all that water into the cabin filter duct and the rear footwell area. I am testing the fix in rain today. I may need a new tcm. a new torque converter, a new tranny :mad: , then again I may not need anything ;) if she up and runs good. Right now I just need time to get her all together , and will report back. Faith folks , faith.
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
you did of course take the tcm out of its aluminum case before you washed it. let air dry for a day, then brush off all the light residue particularily on ic's. you can use alcohol with a cue tip as well. don't forget the underside of the circuit board
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
The rear footwell is lower than the front, so if you have a flood don't forget to check rear footwell for water
 

jonbergga

Active member
Joined
Aug 8, 2004
Location
Alpharetta, GA
TDI
2005 Passat TDI GLS, unchained
I repaired the plenum gasket only to still have a leak after the work.

Turns out that the shop my PO used to clear his sunroof drains had managed to disconnect the right front drain tube from the lower drain boot - the one that makes the 90 degree turn to exit through the door frame metal and exit the vehicle.

They probably used compressed air to blow out the tube, and it just popped off the lower fitting.

Took a bit of sailor linguistics and contortionism to get it reconnected, but its been fine for 3 years since.

JB
 

Turbospool

Veteran Member
Joined
Sep 15, 2007
Location
Daleville Va
TDI
2001 White TDI Jetta, 280k, 2003 jetta 270k
you did of course take the tcm out of its aluminum case before you washed it. let air dry for a day, then brush off all the light residue particularily on ic's. you can use alcohol with a cue tip as well. don't forget the underside of the circuit board
Thanks for all the good advise here ...... got it all together and discovered water still got in :mad: so yeah ... I needed to go further and get that tough plastic cabin filter holder out and sure enough... there I found the outer gasket in bad shape... replaced it and added some silicon caulk on top of my new gasket to ensure a better seal. replaced everything and WOW !!!! My car runs great again. Just need to find someone with VAG to take my cel off yet. Thanks everyone !!!!!:)
 

Turbospool

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Joined
Sep 15, 2007
Location
Daleville Va
TDI
2001 White TDI Jetta, 280k, 2003 jetta 270k
Seems all is not as well as I had first hoped. After 7 days of smooth shifting.... all of a sudden I'm back to slam bang reverse and poor pulling up a grade .... I'm back into tearing this module up again tonight and will see if things are damp down in there again. I am planning to use some Dialectic greese on the umpteen pin plug and see if things work again. I may give it another real good dry job in hopes things behave .... just hoping the tranny has not been compromised .
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
I don't think slam bang reverse is caused by anything in the tcm, If you get hesitation getting pressure after shifting into reverse, many things could cause it, from low fluid to and including clutch "D" failing or the drum D fracturing, causing a pressure leak. How many miles? Has the pan ever been off to service it? dielectric grease is not the thing to use...dielectric translates to "against electric" You would be better off buying some deoxit at radio shack and use that..Trans slipping going up grades or poor engine performance?
 

Turbospool

Veteran Member
Joined
Sep 15, 2007
Location
Daleville Va
TDI
2001 White TDI Jetta, 280k, 2003 jetta 270k
I don't think slam bang reverse is caused by anything in the tcm, If you get hesitation getting pressure after shifting into reverse, many things could cause it, from low fluid to and including clutch "D" failing or the drum D fracturing, causing a pressure leak. How many miles? Has the pan ever been off to service it? dielectric grease is not the thing to use...dielectric translates to "against electric" You would be better off buying some deoxit at radio shack and use that..Trans slipping going up grades or poor engine performance?
When I place the gear selecter into reverse it goes in with a bang... not a smooth shift as usual.... sometimes pulling up a grade it will slip .... as in throttle without wanting to go. Otherwise things seem fine. I did get the carpet up again and things were damp again probably from washing the car. I am drying things up again. I'm miffed as to how the water gets in there. The wireing was wet again, although the TCM was dry. Thanks
 

Turbospool

Veteran Member
Joined
Sep 15, 2007
Location
Daleville Va
TDI
2001 White TDI Jetta, 280k, 2003 jetta 270k
Ok... here's hoping this will be my last post on my experience here. I dried things out real good again. Sprayed the countless wireing with electrical water dispensing/repelent spray, (fishers auto product) . Took my pollen filter housing back off and replaced the new gasket material with Butyle tape caulk and snugged back down. Tested with a bucket water over windshield .... and things stayed dry. Started up the car only to find it shifted rough as ever. Drove it for 2 mile thinking I am doomed for the tranny shop now. It occurred to me to restart the car. And she worked like new!!!:D Has been working and shifting like a dream ever since. Here's my advise
1. Use only VW gasket or Buylte caulk to replace wore out gasket on Pollen filter housing.
2. Make sure everything is extreemly dry and protected with electrical connecting spray under footwell.
3. Restart car before concluding all is still bad. ( I counted to 10 before restart to allow computer to reset it self.
4. Pray :D
 
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