103tdi broken manifold studs, loud screeching whistle under power.

**Tone13** · 19-03-2020, 05:27 AM

Hi all,

My 2009 Octavia 2.0TDI makes a very loud screeching sound when under power which seems to go away when the engine is at full operating temp. If I stop for a few minutes with engine off, it will do it again briefly and then stop again so the engine doesn't need to be completely cold for it to happen.
Anyway, it was due a service so I asked my local mechanic to see if he could see where it was coming from.
On picking up the car, he seemed to think it was coming brom the back of the engine and was air escaping from around a few manifold studs which were apparently broken. Where the manifold and turbo meet?
He has never had to replace these in a 103tdi but being toward the rear of the engine, thought it could be a big job and may require engine removal.
Any one had similar issues? If it is the manifold studs or manifold gasket, what involved in getting this fixed?

Cheers.

**Lucas_R** · 19-03-2020, 09:11 AM

A loud screeching sound when under power will be boost leaking - and if the mechanic has located broken/missing studs where the turbo and exhaust manifold bolt together then this is most likely where the issue is. When the engine / turbo get hot, the metal expands slightly and this is why the screeching sound goes away when the engine is hot but then comes back when you park the car for a short time and then drive again.

If the manifold studs are either missing or broken (snapped) then that's evidence that someone has tried to do work in that area previously, as the studs don't just break on their own.

**Tone13** · 20-03-2020, 08:32 AM

Yep, that was the consensus....although, I bought the car a few months ago and there was no squeal. Having done around 8,000kms since buying the car, there is now a squeal and no one has worked on the car in that time.

Anyway, I found this video on how to remove the exhaust manifold and turbo from a VW TDI. Looks like a slightly older engine but layout looks similar. Any ideas if the process is the same as it doesn't look too hard.

YouTube

**Lucas_R** · 20-03-2020, 08:55 AM

It may have already had a very small (un-noticeable) leak, and over the past few months it has now started to burn the gasket out making it a bigger leak and more noticeable. Hard to say for sure without seeing it first hand but this is a possible situation.

**Tone13** · 20-03-2020, 09:09 AM

Yeah, true.

**Tone13** · 25-03-2020, 04:01 PM

Saw a Scout yesterday drive past me and it made the same noise as mine. Could this be a common issue?
Any chance a moderator can move this to the diesel engine area as I might get more responses from there being a shared engine with the golf...