2007 T5 AXE Turbo overboost issue - recommend a Sydney mechanic

[hotballs]

I had exactly the same thing in my 4motion multivan 2007 model 2.5TDi , it was the particle filter that had broken and 'dammed ' up the exhaust. While apart, the exhaust manifold was replaced as it was warped and the turbo as well, as the garage i bought it from paid the [arts and said while im in there do it. But i am convinced that just emptiing the broken bits out of the particle filter would have cured it.

[miffymiffy]

I have this issue regularly. Im not convinved this is the fix, however it is temporary and works wonders for me.

Pull off the MAF and MAP (or boost pressure) sensors and spray them with brake cleaner. Ones attached to the air box, the other is under the coolant overflow. Clean them up real good. Plug em back in and enjoy the next 15000km...

[formatview321]

The N75 valve is working.
The EGR was cleaned a year ago and looks fine.
The turbo actuator also feels ok.
Cleaned the MAF/MAP - cheers for the tip miffy.


From discussions online and with a specialist VW mechanic it appears to be an issue with ‘sticky vanes’ on the turbo. I have sprayed some oven cleaner into the turbo from the exhaust side and still need to do some driving to determine if this improves things.


One issue I have is that under hard acceleration the intercooler hose popped apart at one of the joints after the EGR and before the intercooler, right under the coolant reservoir. This has led to an endless cloud of black smoke out the back under load, until the pipe is reconnected.


Now, I have seen these EGR blanking plates mentioned and I am wondering if installing a blanking plate would help to alleviate this issue that I am having? Would that stop the excess pressure from the turbo or could that just result in the pressure breaking something else?

[Rebuild]

I tried oven cleaner on mine years ago, don't think it did anything. But then, my turbo wasn't acting up either. Just i had the pipe off, thought i'd try it.
I have an EGR plate in my 2004 AXE, which is a mechanical vacuum operated EGR. It does not throw an engine code.
Blanking the EGR has given a little extra low/mid pull.
Around 2007ish i think T5's went to an electronic EGR. Blanking these EGRs will likely throw an engine code or dash light. Not sure if this can be coded out or overridden. Someone else will likely know. Check which type of EGR valve you have before even trying a plate.
I don't think a plate will fix the issues you are having.

[formatview321]

Yeah I was hoping a blanking plate could at least stop the intercooler hose from bursting.
At this point I've ordered a new N75 valve and MAP sensor just as they a cheap, DIY option to rule out any issues. I'm likely looking at either needing to have the turbo reconditioned or just get a new one.

[Rebuild]

regarding the hose joints separating, the clips and pipes wear over time. Always make sure the clips are fully seated.
I think someone on here has even resorted to using selftapper screws to hold things together

[Sunny43.5]

regarding the hose joints separating, the clips and pipes wear over time. Always make sure the clips are fully seated.
I think someone on here has even resorted to using selftapper screws to hold things together

That may have been me , our intercooler hose started to come off with loss of power and lots of smoke . The circlip wears the flange as the hose pulses back and forwards until the circlip no longer holds ,being a tight arse i could not see the value in replacing the whole assembly at the time of around $700 so a couple of screws did the same job for the next ten years and a far as I know they are still holding longer than the circlip ever did with that vans new owner .

[Silver Caravelle]

I have also used the self tap screw method, but a bit of pain to drill hole and do, due to tight access. Actually the deaIer did it some years ago I recall.

I wonder if another simpler option is to thicken the circlip by wrapping some thin wire around it or sliding on a spring or something ( or a thicker clip) to regain a snug fit with the worn flange.

Cheers, Scott

[formatview321]

Thanks Sunny, thats a great tip on the circlips. I might even use pipe clamps if it comes to that.