LEON cupra TDi oil catch tank

benhampshire

Active Member
Jun 29, 2008
107
0
Barnoldswick
Hi All,

Been doing some work on the leon lately and i just thought i'd post.

Some things have been posted previously but hey theres always those where search doesn't work!

2 weeks ago i cleaned out the intake pipes and egr valve... what a mess!

Nearly 3hrs and 2 cans of carb cleaner i had what looked like to be a nice shiny egr valve.... noticing how much crud had built up i didn't want this to happen.

Doing a bit of searching for stopping this on the forum i found 2 ways:

1.) Remove the vac pipe and block off

Did this, instant EML light but the car ran better!​

2.) Found a method by Glynnd of a gasket with a 4 -6mm hole in it on teh exahust feed to the exhaust cooler.

Did this, not an instant EML light but took 25 miles or so, not too bad as i have my scanguage constantly hooked up and vag come so quick push of a button and its gone again for another 20 miles or so.​

Feeling happier and car running smoother i wondered about the oil vapours from breather to the intake. Again a bit of searching on this forum found that catchtanks are pretty easy to do.

Hmmm lots of threads for the petrol cupra on this one but not tdi. :headhurt:

So here goes:

1.) Obtain catchtank off ebay... £30 - check
2 x 15mm inlet/outlet not one with a crappy filter on top

2.) Obtain 25mm silicone hose to sleeve off the crank case breather and also sleeve the T.I.P intake 'nipple' (you gotta laugh at that word lol ;) ) about £8 for 1 mtr off ebay

3.) Obtain 15mm 2mtr hose from ebay to place inside your 25mm sleeve and route to catch tank

4.) Everything arrives and you wonder how to fit the bugger :think:

After playing around in teh engine bay its not as simple as the petrol as theres not as much room.

I eventually decided on the bulkhead/firewall on the passenger side near the fuse box and between the n18/75 valve grouping (as you can see in the pics)

To do this i needed to build a bracket in the shape of an upside down 'U' this was to place the catch tank far enough way from waht i believe is something to do with AC filling/bleed valve?? (can someone correct me on that)

It was then a simple case of bolting it together and plumming in... now i'm hoping someone can assist here. The petrol guys are on about another breather which yuo need to t off from further down the engine but i couldn't find that so i'm not sure if the pd150 tdi has one or not. Either way have a look at the pics and let me know what you think.

Only being on for a couple of days it appears to have mainly catched oily water vapour...?

I now get very little steam/smoke on cold start-up and i'm hoping my intercooler may thank me for this later on.

Pics as promised:



 
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benhampshire

Active Member
Jun 29, 2008
107
0
Barnoldswick
i was also think of perhaps running a small pipe to the bottom of the catch tank on the inside from the inlet to help condese the vapaour... not sure how yet though?
 

benhampshire

Active Member
Jun 29, 2008
107
0
Barnoldswick
I found the catch tank made my car smokey. I will be selling mine soon.



Not sure why that would be case... you have less impurities going back into the intake so you should get less smoke.

If you are breathing to atmosphere rather than back to the intake the ecu proabably expects a certain amount of return gases as its after the maf so unmetered (i think).. if its not getting them you might have slight over fueling or boost leak etc.

The point of a catch tank should in theory cause less smoke... I wouldn't give up on it so quickly.

Just my thoughts on that....
 
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jonjay

50 Years of 911
Jun 27, 2005
5,843
1
Essex
Not sure why that would be case... you have less impurities going back into the intake so you should get less smoke.

If you are breathing to atmosphere rather than back to the intake the ecu proabably expects a certain amount of return gases as its after the maf so unmetered (i think).. if its not getting them you might have slight over fueling or boost leak etc.

The point of a catch tank should in theory cause less smoke... I wouldn't give up on it so quickly.

Just my thoughts on that....
In theory yes - I thought the exactly same as you but I am not the only one. UncleFester and ChrisGTL have removed theres due to causing smoke issues.
 
Mar 8, 2007
831
0
I have read that a lot of the problem with them is that they cause too much excess backpressure, because the inlet and outlet just aren't big enough.
 

benhampshire

Active Member
Jun 29, 2008
107
0
Barnoldswick
So does your Engine management light still come on with the oil Catch tank on there?


Yeah but its not due to the catchtank thats due to the computer thinking the egr valve isn't working correctly. It is but its due to the gasket with a only a small hole in it. The pressure differences, temp and marf difference cause the computer to realise something different and throw an eml.

If i hadn't done the above and just fitted the catch-tank there would be no eml. Theres nothing to say you can't do this, i personally found that the car ran better with egr basically disabled. With it is being the pd engine i can't turn it off in vag com so this is the next best thing. Completely blocking off the vac pipes caused an instant eml.

The onyl way to get around this is to get it mapped out i believe so that will have to wait till stage 2 :-(

As i previosuly said though fitting a catch tank shouldn't cause an issue with engine management, and as long as you feed back into TIP i can't see the back pressue issue existing. Breathing direct to atmosphere could cause an issue with that though....

Again just my thoughts nothing to say i'm right! :shrug:
 
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ChrisGTL

'Awesome' LCR225
Nov 17, 2007
2,459
2
Huddersfield
Mine was vented to atmosphere.

DSCF0916.jpg





God rid after my exhaust started puffing out thick smoke when booting it.
 

benhampshire

Active Member
Jun 29, 2008
107
0
Barnoldswick
i think breathing to atmosphere maybe part of the issue....

Anywho just moded the inside of my catch tank... placed a small pipe on the inlet side on the inside of the catch-tank.. this should help the vapours condense and drip out at the bottom of the tank rather than the top.

How many of you are bored now... lol
 

Andrewcupra TDI

Resident Desk Jockey
Apr 30, 2008
3,282
2
in the mountains ( Wales )
theres on on ebay that says for the pd engines but not pd150 ?? thought they were universal ,

i dont wana blow 50 - 60 not for it to work ,

or if someone can draft a whats needed list and if poss links - much appreciated

cheers

andrew
 
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