Turbo whine on C5

citrokid · Post by **citrokid** » 22 Apr 2011, 22:55

noticed that the turbo on 1.6 C5 hdi has a whine (not much) when at about 2500 rpm.
What is this an indication of ??

Post by **CitroJim** » 23 Apr 2011, 11:17

If it's boosting properly, running well, the whine is just audible and does not sound 'nasty' or rough, nothing very much normally. Some can be audible like this and I well recall my Turbo Metro of many a long year back making quite a satisfying turbo whine...

It may be worth an oil change if the oil is on the elderly side.

A whistle, rather than a whine, indicates a boost leak...

citrokid · Post by **citrokid** » 23 Apr 2011, 22:02

CitroJim wrote:If it's boosting properly, running well, the whine is just audible and does not sound 'nasty' or rough, nothing very much normally. Some can be audible like this and I well recall my Turbo Metro of many a long year back making quite a satisfying turbo whine...

It may be worth an oil change if the oil is on the elderly side.

A whistle, rather than a whine, indicates a boost leak...

Oil changed today !! have not driven the car other that a few miles - no change
it is working well, no change in car performance, the whine sounds like a siren many many miles a way, almost faint. I wonder is my whine the same as a boost leak?
if so where is the most likely location of the leak?

Deanxm · Post by **Deanxm** » 23 Apr 2011, 22:37

whine is usualy because of a poorly ballanced turbo charger but then some turbo's do make noise and some as Jim says do not, if you do have a boost leak though it may be worth checking over all the boost pipes to make sure they are securely fastened first and nothing has chaffed through them.

D

citrokid · Post by **citrokid** » 23 Apr 2011, 22:57

Deanxm wrote:whine is usualy because of a poorly ballanced turbo charger but then some turbo's do make noise and some as Jim says do not, if you do have a boost leak though it may be worth checking over all the boost pipes to make sure they are securely fastened first and nothing has chaffed through them.

D

i will check over all the pipes tomorrow,
would a turbo go from being a quite unit to a noisy unit over a few weeks /months

Deanxm · Post by **Deanxm** » 23 Apr 2011, 23:02

i dont think so no, centrifugal force would ensure any oil or carbon on either the compressor or turbine wheels was distributed evenly so it would not become unballanced in use.
Have you noticed a lack of power or economy at all recently?

D

Chlorate · Post by **Chlorate** » 24 Apr 2011, 02:30

The engineer within me screams a little whenever centrifugal force is mentioned

But you're right, they spin at around 150,000 RPM so crud on them wouldn't settle in a way that could put the turbo out of balance over use. Although if something could make its way past the air filter somehow, it could do a fair bit of damage to the compressor.

However since the bearings are hydrodynamic bearings they do get a bit fussy if the engine's lubricant is ignored for any length of time, or if you don't let the engine idle for a bit before turning it off.

If the power or economy hasn't suffered though, it's probably not something to worry about.

dnsey · Post by **dnsey** » 24 Apr 2011, 07:38

My C5 turbo also sounds exactly like a distant emergency siren at times, and has caught me out on a couple of occasions, looking for the blue lights!
I'd say it's perfectly normal, and nothing to worry about.

fynnbar · Post by **fynnbar** » 24 Apr 2011, 13:02

It is, however, a sign that the turbo bearings are wearing, and it will get steadily worse.
Mine has been doing so for about 2 years, and I now think it's time to replace it.

citrokid · Post by **citrokid** » 25 Apr 2011, 22:38

fynnbar wrote:It is, however, a sign that the turbo bearings are wearing, and it will get steadily worse.
Mine has been doing so for about 2 years, and I now think it's time to replace it.

Deam xm - No noticable loss in power and mpg is good .

fynnbar how many miles is 2 years - i do about 20- 25K p.a.

fynnbar · Post by **fynnbar** » 26 Apr 2011, 06:43

20-25K in two years. Don't travel as far as you ...

citrokid · Post by **citrokid** » 30 Apr 2011, 20:54

fynnbar wrote:20-25K in two years. Don't travel as far as you ...

thanks for the info