FuZzBoM

Hi all,

first of all, please don't flame me for asking for help on this.. I have literally tried everything and run out of ideas. hoping some of you guys can suggest anything.

will give a run down of the issue. The car started making an odd chirping noise. my mate who owns the car kept on driving it anyway. (Stupid I know)
well no surprise the turbo literally shat itself. I have never seen a turbo go so impressively. exhaust and intake impellers with chunks missing and the internals hanging out.

So, New turbo fitted and the car is still making the noise. on the Corsa VXR the turbo is part of the exhaust manifold with wastegate and recirculation valves attached. As such these are both new items.
Car will drive but if you get to any kind of boost it feels very held back. letting off the throttle is when this chirping noise happens and whole car seems to jerk.
we are worried the chirp is the impeller stalling due to too much exhaust pressure?! We thought the wastegate BCS was to blame. took this off and it operated as we had expected with a 9 volt battery.
vacuum lines all ok etc.

car idles perfectly. sounds spot on until you get to boost level of RPM.

during this whole ordeal there has not been a single EML... good old Vauxhall lol.

any ideas more than welcome.

cheers,
Rob

the shreksta

iTrader: (20)

Speak with regal/Courtney sport and ask on migweb aswell

Maz

iTrader: (34)

Sounds as if there is a restriction post compressor. Something that should have been investigated BEFORE the turbo change. Check piping, intercooler etc. basically everything post compressor outlet to inlet.

FuZzBoM

intercooler has been off. checked over and cannot see anything obviously wrong with it. all pipes ok. no holes or blockages etc.
the turbo exhaust out goes directly to the cat in the down pipe. also removed and not full of shredded metal and also looks to be ok.
I am not convinced the BCS is working as it should tbh. I want to get hold of a manual boost controller to test this theory.

I also have an audio file of the noise it makes.
https://www.dropbox.com/s/uovd16brrr...A0000.aac?dl=0

FuZzBoM

cheers shreksta, i suggested this to the owner of the car.. not sure if he has done that yet.
I know he has asked on a VXR forum but has not had any luck. they do not seem to be as mechanically minded as the bunch on here.
This is the reason why i thought I would ask on here. I dare say for many a Subaru is not the 1st turbo/performance orientated vehicle people have owned, I am sure there is a wealth of experience and knowledge

FuZzBoM

Had an idea to eliminate the BCS.. would there be any issues in bypassing it and running the vacuum line direct from the turbo outlet direct to the wastegate? ok I know it will probably not hit as higher boost as with the BCS in place but should in theory stop it overboosting (like I think it is)? thus proving if the BCS was at fault?
I have noticed some turbo's come like this already, especially the cheap Chinese TD05's etc.

Infected by sti

iTrader: (6)

Have you checked the plastic vac line that runs from the actuator T, down the drivers side of the engine and on to the inlet underneath, they can get brittle and snap.

It makes that kind of chirp you talk about when you lift off and will struggle to make boost.

Does it have a boost gauge, if so what boost does it make? It will struggle to make any kind of positive boost if that's broken, or it has in my experiences.

FuZzBoM

yeah we have had all the vacuum lines off and checked them over. all seem to be ok.
taken the Vacuum box thingy off and only allows air flow 1 way as expected.
taken the BCS for the recirculation valve off and again tested as expected as are the lines going to it.

Does not have a boost gauge but I do have OP-COM and that registered a max of 104 kPa, roughly, 15psi from what I can gather. This is assuming the boost sensor is also working correctly.
I have ordered a boost gauge as want to run one on my car so can test properly with that when it arrives.

cheers,

bengo

iTrader: (17)

Have to you checked to see whether the turbo getting oil?

Carnut

Would it working under pressure make a difference?

What about this http://www.vxronline.co.uk/forum/sho...valve-sticking
A £6 cleaner isn't too big a stretch of funds.

FuZzBoM

Bengo - yes.. by accident lol. we started the engine without the turbo attached and it squirted out the oil feed we also primed the new turbo before fitting it.

Carnut - we have wondered the same. We blew down the pipes while supplying power and it seemed to operate ok but human puff probably isnt enough to highlight any issues?

A little further on in the thread it says the corsa VXR does not have an EGR.. and I could not see one either when I looked.

My mate has informed me he has ordered a new wastegate BCS, I guess we have that to try next when it arrives.

Carnut

Oh right, l only read the first post on the vxr thread.

My wife is pretty good at blowing, l could send her round as long as you don't send her back.

FuZzBoM

Latest update, BCS replaced. This has not fixed the problem but does seem to have reduced the 'chirp' noise a bit!?
I think next we need to vacuum test all the lines and possibly replace a few to eliminate them. Probably another weekend under bonnet of a corsa VXR lol.

FuZzBoM

I have to retract what I said before.. does indeed looks to have been oil starvation. Pulled the feed line off and indeed blocked!
cleared it and now runs like a champ.

all advice was very much appreciated. cheers guys.

Dave Y

iTrader: (52)

I do like a happy ending.

bengo

iTrader: (17)

Glad it's sorted