Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off

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Tue 6 Jul 2010 21:58
Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off - mikejharvey

My Astra 1.3 cdti (Fiat engine) has started making a strange vibration / humming noise when I switch the engine off once thoroughly warm. The noise persists for 10 seconds or so after the engine has stopped, and it comes from a small component situated under the offside front chassis leg, just forward of the front subframe mounting, more or less under the headlamp, but back a little. The component is mounted on rubber bobbins, and has a wiring loom plug attached. Have any of you guys any idea what it is and what it does, and is it potentially serious? I'd be very grateful. Cheers

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Tue 6 Jul 2010 22:12
Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off - Collos25

Is it something to do with the electric steering set up I have heard of these units burning out on Puntos.

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Tue 6 Jul 2010 22:45
Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off - mikejharvey
I don't think so Andy, but who knows! Mine has a hydraulic reservoir on the n/s of the car almost on the end of the rack, down behind the engine and I think it's probably electro hydraulic. Strangely enough though, the power steering can sometime stake 8-12 seconds to come on even when the engine is running. I complained when it was still under warranty, (it's a 2007) and they have just made a note in case it develops.
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Thu 8 Jul 2010 18:25
Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off - dervdave

The wifes 58 plate 1.3CDTi Astra did the same, itsan electrical component powering down but can`t remember what it was.

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Sun 25 Jul 2010 17:38
Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off - Znorkas

I too have have the same engine, Opel Astra 1.3 CDTI.

I have the exact same noise coming from the exact same place (the offside, my car is LHD so it's coming from the front right somewhere). I can't make out what is making the noise, it's hidden somewhere (the airbox takes up most of the real estate there) but it comes on after engine turnoff and buzzes for 10 seconds until it fades away. It's quite loud.

Car is scheduled for a regular service tomorrow, I'll ask my garage if they know what it might be. I wonder why it has only started appearing in the last month or so.

Edited by Znorkas on 25/07/2010 at 17:38

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Mon 26 Jul 2010 17:10
Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off - Znorkas

So the car went in today and once I stopped at the dealer it was silent! For the first time in weeks! Figures, what's that law called, Murphys isnt it? Perhaps it was feeling at home. After the s

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Mon 26 Jul 2010 18:01
Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off - Znorkas

Hmpf the forum cut me off and it won't let me edit my previous post so here comes the rest..

So the car went in today and once I stopped at the dealer it was silent! For the first time in weeks! Figures, what's that law called, Murphys isnt it? Perhaps it was feeling at home. After the service, when I stopped at home though, sure enough the sound was back

Anyway, as the sound didnt manifest itself while it was at the garage, I had to describe it to the Opel man and he figured it was an electrical component powering down and guessed it belonged to the air conditioning. Strange however if that is correct, I as this air conditioning problem seemingly only affects 1.3 Fiat engines... (?).

Isnt it weird how intermittent faults always disappear when the car is at the dealer?

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Wed 18 Aug 2010 00:04
Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off - smh

I have had exactly the same noise on a 57 plate 1.3CDTI. The noise is the EGR modulator which is located beneath the air filter. The modulator controls vacuum to position the EGR valve and the noise is caused by vacuum being released when the modulator is powered down. Mine was replaced this week under warranty and so far I have not heard the noise again. I'm assuming that although noisy when releasing vacuum the modulator/EGR was operating normally as I was told t was OK to drive whilst they waited for the part. Hope this helps.

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Sun 5 Sep 2010 12:20
Vauxhall Astra H Estate - Astra 1.3 cdti strange humming on switching off - Znorkas

Thanks for your comprehensive reply, it helps alot! It's nice to know what it's coming from!

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