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Turbo Noise
Posted: Thu Mar 29, 2012 12:41 pm
by rlees85
This is gonna sound stupid but...
When the turbo starts to spool up you can hear it tssshhhhhhhh
obviously this noise gets louder and you can hear it as it boosts more and more... (as your revving through a gear)....
then at very high boost you can hear it: ssh ssh ssh ssh (obviously sounds like the turbo noise, but on and off like the sound of a petrol engine hitting its rev limiter if you know what i mean)
is this normal for a VNT?
or does it sound like a buggered turbo?

Re: Turbo Noise
Posted: Thu Mar 29, 2012 1:31 pm
by Doggy
No. Sounds like a normal VNT, that's been remapped.

Re: Turbo Noise
Posted: Thu Mar 29, 2012 1:40 pm
by lozz
My 110 sounds abit Hissy,
was ok before it was Re-mapped, ijust turn the radio up,

Re: Turbo Noise
Posted: Thu Mar 29, 2012 2:15 pm
by Welly
Could be the start of the bottom intercooler hose failing (they can wear a hole underneath) caused by excess engine movement, caused by worn mounts.
Re: Turbo Noise
Posted: Thu Mar 29, 2012 3:22 pm
by rlees85
It hasn't been remapped yet! only de-fapped... its not the hissing thats bothering me, my old 306 HDI used to hiss like a pissed off snake and i like to hear my turbo working ;) its just the weird shh-shh-shh-shh (like the noise is on and off very quickly) on full boost.... but if its normal for a VNT then thats all good
all my intercooler pipes are going to get attention soon as im going to try and do away with the intercooler bypass stuff and will check the other pipes whilst im at it so maybe something will come up there too
Re: Turbo Noise
Posted: Thu Mar 29, 2012 3:24 pm
by rlees85
sounds a bit like mutleys laugh speeded up! to give an idea !
Re: Turbo Noise
Posted: Thu Mar 29, 2012 5:06 pm
by lozz
Have a listen round the Egr area.
the v reg 406 ihad ~hissed a little bit from the valve on the Egr.
only slight but noticable, igave it a tap with the handle end of a big screwdriver, and it cured it,
Re: Turbo Noise
Posted: Thu Mar 29, 2012 5:14 pm
by grasmere59
I'm on my second 110 and they both sound totaly different from each other when the turbo spools up.
Re: Turbo Noise
Posted: Thu Mar 29, 2012 5:54 pm
by Doggy
rlees85 wrote:It hasn't been remapped yet! only de-fapped... its not the hissing thats bothering me, my old 306 HDI used to hiss like a pissed off snake and i like to hear my turbo working ;) its just the weird shh-shh-shh-shh (like the noise is on and off very quickly) on full boost.... but if its normal for a VNT then thats all good
all my intercooler pipes are going to get attention soon as im going to try and do away with the intercooler bypass stuff and will check the other pipes whilst im at it so maybe something will come up there too
Mine's always done that. Pretty sure I don't have any significant boost leaks. It does collect a fair bit of oil at the bottom of the intercooler and few traces at the throttle bodies, but I think that's OK after 170+k. You've probably also noticed the low-speed whoosh is much more prominent when the engine's cold & bypassing the intercooler, again, that's normal. (I've occasionally thought it was an ambulance siren)!

Re: Turbo Noise
Posted: Thu Mar 29, 2012 7:52 pm
by rlees85
Put a new EV on today on the turbo and it seems to be up on power so far

still a lot of lag though!!
I took the hoses off both the air dosers to check they were in the correct positions, which they were but they were oily! it wasnt clogged but it wasnt traces either.. all the walls of the hoses and dosers were slippery :/ first thing I did was check my oil but it hasn't gone down, maybe a tiny fraction over 2,000 miles.... not sure how normal that is, or if the car had a previous turbo failure that made the mess.
as for the intercooler, i noticed both hoses are in the middle of the intercooler (not bottom or top, just one on one side going in, and one on the other going out) so how would I drain that off? please tell me there is a drain plug and i've not got to remove it from the car

lol!
the mutley laughing noise is different to a constant whistle by the way.... and was more worried it being a fudged VNT mechanism or something, but after some reading I think this would cause overboost and all sorts...
getting closer every day

Re: Turbo Noise
Posted: Thu Mar 29, 2012 10:31 pm
by Doggy
Sorry, forgot yours was a coupe - (they have different intercoolers), the saloon / estate one is about 125 mm square x 400 mm high, mounted to the side of the radiator / condenser......
The oil is a combination of minor seepage past the turbo seals and possibly some breather fumes. Mine will almost do 12.5k between oil changes without any topping up, (sometimes it uses a cupful in those miles), but that's enough to make it look pretty oily arnd the intecooler / dosers etc.
(Sorry, don't know if there's a drain plug, suspect not).
Re: Turbo Noise
Posted: Fri Mar 30, 2012 11:26 am
by rlees85
The coupe one is massive, it fits in between the radiator and the condensor... im sure it would be radiator off to remove the intercooler so i hope to god theres a plug on it... ill have a good look for one, if not ill do it when i sort out the rest of the intake. cheers for help!
Re: Turbo Noise
Posted: Mon Apr 23, 2012 5:58 pm
by rlees85
ok i need your opinions please! turn up your speakers niiiice and loud (no this isnt one of those stupid make u jump things)
http://youtu.be/aYkS-f5Qjgk
Turbo starts spooling at 4secs (sounds alright!)
Gets to high boost at 6 secs and starts making stupid noises!
You have to really listen for it though. What is up with it that would cause it to make this noise? (along with the random power issues im still having)
Re: Turbo Noise
Posted: Mon Apr 23, 2012 6:09 pm
by lozz
My ears arnt up to much,
didnt notice anything, other than a Hiss, slight blow perhaps?
Re: Turbo Noise
Posted: Mon Apr 23, 2012 6:52 pm
by rlees85
Its a really hard sound to record as the car has to be moving (under load) and if I hold my phone out the window it just gets wind-noise...
That clip has to be played loud, it starts with a nice normal hiss from 4 seconds, then at the end of the 6th second the hiss starts chopping up until about the 8th second. I can't logically think what would cause a turbo to do that.