2007 TDCi Focus - Wierd engine noise

~Spyne~ · 04-09-2012, 08:43 AM

Hi guys, before I take the car in to Ford to get their assessment, I thought I'd ask here...
The car has done 117,000km and is due for a service this month, but in the last couple of days I have noticed that when I turn the car off, the shutdown noise of the engine has changed quite a bit.
Rather than being the higher-pitched, brief noise you should hear of the turbo? shutting down for 2-3 seconds after you turn the ignition off, it's now become a lower, deeper pitched noise which kind of sounds a LOT like someone squeezing out a fart.

Bit hard to explain properly, but that's the best I can do without recording it and uploading a sound file.

Anyone have an idea of what this could be?

AlanD · 04-09-2012, 02:53 PM

Hi,

Our Mondeo

(see sig) has has a similar noise on shutdown since day 1. Since it has now done 40,000+ km in that time I've begun to regard it as being "What normally happens".

But the car will be geting a 4 year extended warranty in a month "just in case".

I thought it was the turbo running down, but other in the Mondeo

sub forum have said they think it has something to do with the ventilation system closing/opening baffles/vents.

Who knows? There has been no alteration in how the car works, so I'm going to regard it as one of those mysteries you will probably never get a good explanation for.

Cheers

~Spyne~ · 04-09-2012, 02:56 PM

Thanks Alan.
I've also not noticed any change in the car's performance, and funnily enough, the shut-down noise was back to 'normal' this morning.
Will keep an ear out for it, and maybe mention it when the car goes in for a service, but as you indicated, might just be 'one of those things'

Turbodiesel · 04-09-2012, 06:07 PM

What you hear spinning down is the power steering motor, the only thing mine does is a bit of a shake when you shut it down sometimes.

rand0mn00b · 04-09-2012, 06:49 PM

my Focus is non turbo and also has that noise, as do many mazda 3s.

i believe it is to do with something in the steering. you will hear a similar noise by turning the steering while stationary

ramondo · 28-10-2012, 04:47 PM

Possibly an air con compressor crack...

I had a similar thing Strange Noise when engine Switched Off

RadioactiveX · 12-03-2015, 03:07 AM

It could also be related to the fact TDCi having VGT - Variable Geometric Turbo. As we know, this kind of turbos have turbine inside that opens and closes depending at what rpm/speed you are on to.
High rpm= high pitch
low rpm= low pitch.
It may be possible that at the time you turn your ignition off with high pitch, from acceleration to park you had immediately turned the engine off while the vanes are still open, opposite if you wait for awhile then you turn engine off while the vane is already closed thus, making the low pitch noise.

disco stu III · 16-03-2015, 06:59 PM

our 07 tdci did this for a while. sounded like a valve (pcv/egr) opening and shutting really fast. assumed it was all chudded-up. maybe the engine oil used by non gen service blocked it up? not sure, but it went away. it did sound terrible. it has also stopped blowing as much zorst smoke when full throttle is used. was assuming it was blow-by. gave it a caning for a few months, no probs now. destroyed a set of cv's though. and a set of tyres too. couldn't see the steering turnout to confirm that theory. front rhs?

RadioactiveX · 16-03-2015, 07:13 PM

How many Kms have you done with it?

Dustproof · 08-04-2015, 08:43 PM

The wind down noise after you shut down is the power steering pump, not the turbo.