One thousand brownie points to who ever may shed some light.

[benclarke]

Boost leak, boost leak boost leak?

My car just isn't running properly.. High revs in 3rd and 4th gear just go no-where and although I dont currently have a boost gauge or a boost leak "tester", this is what it feels like to me.
I have got a brand new 007p and have deleted my N249 properly using silicon hoses tightened up nicely.

I have replaced various vacuum servo hoses that were split. The oil breather hose coming on the rocker was perished, so I replaced it with an awesome-gti silicon jobby.
The breather coming off said silicon job ,down to the the lump was also replaced up until the solid plastic piece. The plastic pipe which connects directly the the lump however is not fitted properly and needs replacing.

Excuse my lack of knowledge in the world of turbocharged engines but will oil breather pipes affect boost in any way?

I have checked the intercooler and associated pipework and the "seems" fine although I have not clarified this with any forced pressure test.

Where do I go next? Obviously because its not perfect I will endeavour to change the plastic pipe coming off the block but are there any other hoses that could be split or any other reasons to explain the car under-performing?

The actual symptom is a jerkey sensation and complete lack of power in 3rd and 4th when you need it most.
Fault codes 17705 and 17545.

As it said in the title, if anyone can lead me down the right route 1000 brownie points will be awarded.

 

[s3dave]

are sure its not the clutch? with it been in the higher gears?

 

[beachbuggy]

1st one is pressure drop from turbo to throttle and 2nd one is fuel too rich. You almost certainly have a boost leak. Faulty dv valve possibly .?

 

[benclarke]

Yes mate its not the clutch. Would a blow in the exhaust cause any issues like this?

 

[benclarke]

The DV was brand new so Im hoping thats okay.

 

[s3dave]

The exhaust and breather would not have the effects of what you are describing, you reaaly need it on vcds to see whats happening, have you checked the orange pipe that comes off the turbo to the hard pipe? also try taking off the tip, and feeling the turbo for excessive play...

 

[benclarke]

Thanks for the advice dave, I will try all of those things tommorow.

I hope its not the turbo

 

[sportstractor]

If the oil breather system can cause problems if it's letting unmetered air into the inlet. Check DV, check n249 valve, check hoses coming off under inlet for splits etc. a smoke test would reveal all if there is a leak

 

[benclarke]

If the oil breather system can cause problems if it's letting unmetered air into the inlet. Check DV, check n249 valve, check hoses coming off under inlet for splits etc. a smoke test would reveal all if there is a leak

Just to add. It just passed its mot.

 

[sportstractor]

That makes not a lot of difference to be honest, mot doesn't check if the engine is fully performing or not

 

[benclarke]

Yeah but it passed emissions, thats what i meant

 

[sportstractor]

Yeah probably would mate as ecu is adapting the fuel trims to compensate for any vac leaks, it's on boost these leaks become an issue. I presume you have vagcom? As you stated fault codes earlier?

 

[benclarke]

Thanks mate, I only have a cheap faultcode scanner not actually vagcom. Im thinking abou tinvestiung in cheap laptop and getting vagcom though.

Drove the car this morning and the problem seems to have gone, although I didnt drive it long or hard enough for the engine bay to get hot.
Is it a possibility that the split (if there is one) just becomes an issue when the engine bay gets hot? Expansion and all that...

Cheers,

Ben

 

[benclarke]

Sorry for bumping my own thread, does anyone have a diagram of the engine hoses and breather hoses?

 

[aragorn]

Unless you have some faulty check valves, the breather system should never see any boost, and so shouldnt be able to cause any boost leaks.

The vacuum pipes streight off the manfold, before the check valves, do of course have the potential to cause leaks.

 

[s5joe]

Get a smoke test done first to find any leaks

 

[benclarke]

What's the best way to do the smoke test?

 

[benclarke]

Maybe I'll go round with a can of carb cleaner

 

[Alais DJA]

Has this car been recently mapped, ?

I only throw this in because mine was mapped wrong orginally and i had no top end power in 3rd / 4th

 

[benclarke]

I havnt had it long so I wouldnt know. Thanks though

 

[benclarke]

UPDATE: The turbo has become very loud through the glovebox area, sounds like some sort of split hose. Could it be the TIP??

 

[s3dave]

you just have to get down and dirty mate and give all the pipes a proper going over,,what may look ok may still be bad, feel all pipes look for greasy residues...

 

[s5joe]

We're abouts are you mate

 

[s3-oz]

I've got similar characteristics to you, feels sluggish in higher gears (I have a thread "Should me S3 be faster) and I also get this loud sucking noise from the glove box, noticed the other day the turbo pipe(??) at the back of the engine bay that connects to the long steel pipe that runs on the left hand side is split, on the underside where the metal pipe ends, this im hoping is my issue as i have bought a silicon forge pipe to replace it. have a look at your pipe mate

 

[benclarke]

I've got similar characteristics to you, feels sluggish in higher gears (I have a thread "Should me S3 be faster) and I also get this loud sucking noise from the glove box, noticed the other day the turbo pipe(??) at the back of the engine bay that connects to the long steel pipe that runs on the left hand side is split, on the underside where the metal pipe ends, this im hoping is my issue as i have bought a silicon forge pipe to replace it. have a look at your pipe mate

Thanks for that mate I will check tonight! Would be great if this was the case.

And joe I live in Worcester mate, yourself?

 

[benclarke]

Oz any chance you could link me to the hose

 

[s5joe]

It's the hose from your intake by the sounds of it. I am from Liverpool but you need a smoke test defo to see we're the leak is.

 

[benclarke]

Stupid question im sure, where do you go for a smoke test?

 

[s3-oz]

Ben the hose thats fubar'd on mine is as follows (dont have a pic unfortunately). on the left of the bay there is the metallic pipe (not sure of its name intake maybe?) this runs up the left and elbows right along the top of the engine then terminates into a rubber "elbow" hose type thing. this elbow is the hose thats bust

 

[s5joe]

Your best haven a look on the net mate.

 

[benclarke]

Ben the hose thats fubar'd on mine is as follows (dont have a pic unfortunately). on the left of the bay there is the metallic pipe (not sure of its name intake maybe?) this runs up the left and elbows right along the top of the engine then terminates into a rubber "elbow" hose type thing. this elbow is the hose thats bust

Cheers for that mate I will have a check tonight.

 

[aragorn]

Most vag specialists should have the kit to do a pressure test or smoke test.

 

[Sandip]

Double check the vac lines under the intake manifold, check the fuel pressure regulator vac line in particular

 

[Benjiman46]

Sounds to me like you have what my mates TT had.. That was a collapsing TIP... Just a thought

Ben

 

[s3-oz]

sorted those pipes ben and now my car is spot on

 

[Scullies]

I have noticed my S3 also feels "tired" in the higher RPM range in 3rd and up. So whipped a boost leak tester together this afternoon and tested the system. Have such a bad leak, it sounds like I'm blowing air through a pipe.
Found the crankcase breather pipe that comes off the oil filter housing is bust, there is a big section missing and the air is flowing out this busted pipe. Hard plastic parts dont last forever in engine bays.
So once I have replaced this pipe, I will test again for boost leaks.