I recently posted about black smoke, i got it sorted at the garage but now im not afraid to put my foot down ive noticed that when im in third the noise of the turbo keeps stopping and starting, its really weird and i cant describe it... It makes a noise, stops, makes a louder noise as the revs get higher and keeps on stopping and starting.. any ideas guys?

Really starting to worry about it.. also the garage noticed that a pipe from the turbo is leaking (the "out" pipe) and my exhaust has a weld in thats cracked and air is coming out.. are they serious problems?

Once again, thanks.

is it loosing boost when you put your foot down?

Nah the boost is fine, it was but i just got a boost pipe replaced and now its fine

Are you getting a rumble through the pedals when it happens as of something is rubbing?? The same feeling when you brake with drilled and grooved discs on??

Not really, the only real sign of something going wrong is how the whine noise stops and starts as it gets louder, its really strange :/ ill check for what you mean tomorrow, but whats the consequences of that? And will it have nothing to do with the exhaust problem or the turbo pipe problem? Thanks

The leaks elsewhere won't help the turbo run how it should so in a way they do play a part in it yes. Have you had any engine management lights pop up?

Is it running flat all the time or only in third? Could be in limp mode, prob the case seen as the pipe had leaks..

well if the plastic pipe (the one I mentioned in pic) has play then that will start rubbing on your pulleys and if they aren't freely working how they should performance will be effected.

Easy way to see of pipe is interfering with the pulleys is to look on the side of it to see any chunks rubbed down from where its made contact

Unplug the airflow meter and see of any change if not it may be that or the connections upto it.

check the connections to the EGR valve, if any of the vacuum pipes are damaged / corroded then the EGR can be on all time which certainly will hurt performance. Its also possible that its a fault with the EGR valve itself so its worth removing the valve and cleaning it , wouldn't hurt to do this anyways if the car has done a fair bit of mileage they do get clogged up.

Get the garage to check boost readings from the airflow meter, if that's low it could actually be your maf sensor faulty, I had a faulty maf sensor and I would drove the car and it would have flat spots.

** I had a faulty maf sensor before and when I drove my car it would have flat spots as if boost has cut off

Thanks a lot mate, its really weird though.. Like instead of a constant sound getting higher, like i said it stops and starts as it gets higher and it does this only in third.. ill do what you say, im going to get a magnex exhaust soon instead of fixing the weld and get myself the pipe for the turbo as you can see the oil whats escaped around it. hopefully they should help resolve it

A quick google of your turbo fault came up with a guy with a 1.9 passat with same problem and someone replied with this:

I'd say its running off the extra fuel added for acceleration and then when it ll settles down again the fuel isn't there - this makes me think the issue with the airflow meter or is a major airleak

Might also be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can do a quick fault find if you unplug the meter and run the engine without it. if the engine condition is the same thenchancesare the meter or the connection to it is faulty

It could be something as little as that sensor tbh it does seem like its being starved, how's the oil??

Oh thanks a lot mate ill check that tomorrow! The oil is fine mate