# Leon Cupra exhaust/boost leak?



## RuneJJ (Apr 3, 2011)

Hello Vortex

This is my first thread and just registered as a user on VWvortex though I have been an eager reader in the forums for quite some time now.










I have a Leon Cupra from 2007 tfsi with the following mods:

APR 3" downpipe with highflow metal cat. 
APR fuelpump.
BSH Pendulum Mount.
BSH Trottle body pipe.
Forge Twintake. 
Forge Front mounted twintercooler.
Forge replacement dump ventil.
Forge Dv returnhose.
Milltek catback non resonated oval.
Sachs race clutch rated 500nm.
Iridium spark plugs.
Tuning software.

I am kinda stuck on the following problem. The engine pulls fantastic and hard all the way but when I declutch the rpm is slow to go down and goes under 500rpm and it has to fight to go back up to normal idle rpm and sometimes the engine stalls especially if I make a right turn, have only tried turning right and having the engine stalling, after declutch and the rpm goes down.

I have had problems with an exhaust leak between the union of the to parts of the APR downpipe right by the metal cat but we managed to seal the leak with som paste and tightning of the strapping band. 
This gave more sound and power and a much better start up on a cold engine, no more leaking sound on start up 
Maybe there still is a small leak there and causing the problem? I did not have the problem with stalling when it was leaking more.
I have ordered new parts from APR through my dealer in Denmark since I also miss the union piece from the apr downpipe to the Milltek catback. There is also a leak there, sod coming out, which we have tried thigtning the strapping bands, which are from a cheap no name downpipe that used to be mounted on the car, when i bought it a few months back. 
We will adress and fix these issues when I get the spareparts from APR. 
We have tried cleaning the forge DV and checked the Forge twintake for leaks but not sure it has made any difference.

I am not sure it is a exhaust leak since the exhaust got a much sweeter sound when we fixed the leak mentioned above. Still it looks like there is new sod coming from where the APR downpipe is joined by the metal cat but not where we have used paste to seal the leak.
There are no DTC codes by the way So not sure if the problem is a exhaust leak or a vacum leak somewhere?
Therefore I would very much appriciate any input that could lead me in the right direction to fix the problem once and for all Sorry for my English. It is not everyday I use it anymore:screwy:


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## RuneJJ (Apr 3, 2011)

Bump

Please help me.


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## ROH ECHT (Dec 9, 2010)

Sounds like you might have more than one issue or you have a couple of things going on as a result of one problem. You might have something going on with your dv and pcv. But both could be resulting from vacuum issues. I'm going to look aroung for guys with similar probs for you...


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## [email protected] (Jul 29, 2008)

Does the issue go away when you unplug the MAF?


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## RuneJJ (Apr 3, 2011)

*..*

Hi guys

Thanks for your reply.

I will try and unplug the MAF and see what happens. I was also thinking a faulty PCV could be an issue since it has never been replaced and the car is from 2007 and probably one of the first versions of the PCV.
I am waiting for spareparts for my bsh street catch which I had on my old MKV GTI 2006. I lost some of the parts for the catch can after taking it of the GTI.

I have tried cleaning and lubing the DV and having replaced the green valve spring with a yellow one but the problem is still there. Also tried Stock ECU/software but stille having the problem.
The problem seem to be getting worse as the engine gets warmer. Idling feels weird as well without the rpm needle moving.


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## RuneJJ (Apr 3, 2011)

*..*

I tried unplugging the MAF but the car just died on start up? Am I supposed to unplug the MAF while the engine is running?


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## RuneJJ (Apr 3, 2011)

*..*

Still crying myself to sleep over this unsolved problem.

Today I scanned the car and got dtc p2196 but not sure it is has been there before or after unplugging the maf?
I dont have vagcom but scanned the car with the box I use to down and upload files to and from the car so I can not give more detail than dtc p2196. Dont understand this code since I have changed both o2 sensors not long ago.


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## RuneJJ (Apr 3, 2011)

*UPDATE please respond*

Installed my BSH Street Catch Can today which have led to new problems and DTC codes.

First of all the rpm rises a few seconds sometimes a bit longer to around 1500-2000rpm when releasing the clutch before reaching 750rpm normal idle speed.

I have taken my time and been very careful installing the catch can the right way so I can not imagine that it is the BSH PCV that is faulty:banghead:









I got the DTC kodes P2196, P119a, P2187 and P0507 in that order. I managed to clear the codes but P0507 was back quickly obviously.

There is two more issues I like to adress and get your take on.
The first is that one of the hoses on the FORGE DV has cracked. Please note that it was not cracked back when I first got the problem this thread is about. The crack in the hose is right where the hose meets the Forge the forge dv thing:screwy: and is highlighted with a red circle in the picture below.
Could this be why I now have the problem with high idle or is this leak/crack not that big of an issue here?











The Second issue is the hose that fits onto the silver thing on the BSH PCV plate does not seem to seal completely. Thinking of buying a new hose, think it is called rear PCV? See picture below also highlighted with a red circle:thumbup:












So please give me your input and advice. I know the next step is probably to find someone with knowledge and vagcom to get a full log on the beast


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## Alidulger (Feb 17, 2016)

Hi. I have the same problem. My car stalls then i clucht in. Have you sort it out ? 




RuneJJ said:


> Installed my BSH Street Catch Can today which have led to new problems and DTC codes.
> 
> First of all the rpm rises a few seconds sometimes a bit longer to around 1500-2000rpm when releasing the clutch before reaching 750rpm normal idle speed.
> 
> ...


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## Maras_66 (Dec 26, 2018)

Hi. Same problem here. Stage 3 mkv gti. New k04, maf, pvc, o2 sensor, map sensor, tb, injectors, hpfp with autotech, dv with gfb dv+. Everything is new. Boost leak test ok. Just exhaust leak im not sure yet. Unplugged maf innsue goes away. No fault codes. Long term trim went from 5% to 12.5%. Thx for any suggestions.


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## Maras_66 (Dec 26, 2018)

Bump


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