Technical Multijet making strange noise

[Samuelb86]

Hi everyone.

My Multijet is making a strange chirping sound and I wondered if anyone else had experienced it?

It only happens if I change gear quite early and accelerate. I thought it could possibly be the turbo but I'm not sure, I've only owned a couple of turbos. It happens in all gears but only under the conditions I've described. It's quite loud, you can hear it with the windows shut.

Can anybody shed any light on it for me?

Thanks in advance. Don't know what I'd do without this forum and the lovely people on it!

 

[Samuelb86]

Anyone?

 

[StiloHal]

Hmmm, hard to diagnose. Do you get the noise when going up hills? Could be clutch, does it bite okay? Could be engine mounts shifting when the engine is loaded. I could go on...
Can you describe the chirping sound a bit more? Is it a high chirp, low chirp?
Does the engine lose power when it chirps...

 

[Samuelb86]

Hi, Thanks for taking the time to reply.

The chirping noise is high pitched. It only happens when I've changed up early and accelerate. It's not the clutch and I don't think it's the engine mounts either. The road gradient doesn't make any difference, it only happens when accelerating from low revs, which makes me feel it could be something to do with the turbo.

Sorry I can't be more specific. I know it's almost impossible to diagnose a noise without hearing it! Just wondered if anyone else had experienced anything similar.

 

[StiloHal]

Ouch, there's a slight possibility it's the turbo vanes catching the housing. The turbo bearing may be worn, allowing play in the shaft and allowing the vanes to just catch, making a shrill noise. (could be described as a chirp)
To check you need to disconnect the air pipe leading into the turbo and wiggle the shaft the vanes are mounted to with the tip of a finger. There should be almost no movement.
How many miles has the engine done and have the oil services been done?

(I've had turbo failure on an Audi V6 TDi and a Ford Fiesta TDCi but not a Fiat so the above may not be accurate)

Good luck and fingers crossed it's something less expensive !!

 

[Samuelb86]

I'm guessing that my turbo could implode if not fixed?

I don't have any service history with the car. I got it serviced and had a Terraclean treatment done when I got the car. The oil was low and filthy when I got the car.
It has been leaking into the coolant which caused a perished pipe and Fiat want £572 just for coolant pipe work and oil cooler.

I'll get my mechanic friend to check the turbo for me and thanks for the advice.

I've had 35 cars in 10 years including 3 Stilos. I spent a lot more on this one that I usually do. Might be a case of running it until the turbo goes bang or another coolant pipe goes (or the cambelt - the coolant was pissing all over that when it burst!)

 

[sussexa]

so the noise is new to you ? or done it as long as you've had the car ?
I think mine used to chirp a bit on changing gear as , it definitely does now but im non std turbo.
id see if there are any local ones similar model for sale and try to get a test drive or any local guys on here to compare the noise to.
with your coolant and oil issue it might be worth dropping the downpipe and inlet pipe off the turbo to get hands on and feel shaft play in the turbo, but as far as im aware the worn bearing police siren whine is us usually more when building or on boost rather than when its dropping boost like changing gear.
you could pull the vacuum pipe off the turbo actuator , plug the pipe and make sure its not hanging down on the road, take it for a test drive and see if the noise is gone.
if it does its most likely turbo related but could just be a noise that's normal to the multijets.(a dealer might call it a charachteristic)
try you tube for turbo surge or lift off turbo surge, sometimes sounds like a weak dump valve type noise on a chav petrol turbo.
I had a vid up you may hear something like it on gear changes, but as I said im a bit too far from standard to compare.

sorry re-read and it is on building boost not letting off, with hands on the center shaft of the turbo a little up n down wiggle movement is normal but any end to end along the shaft is not good basically if you can feel it by hand you have probably too much wear as it only needs 0.5mm movement to catch blades on housings, the wear limit is something like .08-.10mm
I have a vid up showing my old turbo to give an idea how much that is as I show it with a dti


with new bearings in it the axial play was 0.01-0.02mm virtually nothing, and radial play was about the same (the pressurisedoil helps centralise it anyway)
also sometimes a turbine or compressor wheel can loose a tip or chip an edge that can sometimes cause a chirp or whine,

 

[Samuelb86]

All I can say is a huge thank you for taking the time to give me such a detailed reply. I'm going to get my mechanic mate to look at the points you've said (it's a little too involved for my basic DIY skills)
I'll keep you posted

 

[Txuchin]

I think it is easier (and cheaper) begin by reviewing the crankshaft pulley