Hey people.

I'm new to the Briskoda forums but been loving my Fabia VRS for about a year now with no real issues. However.... I have a very perculiar noise coming from the engine when i turn the ignition off.....

The only way to describe it is, it sounds like some kind of pressure releasing and a low frequency noise lasting about 5-6 seconds before dissapearing. You could liken it to a single note trump that lasts... My car sounds like it's farting. I can't work out if it's anything related to the clutch/braking slave cylinders as they de-pressure when the ignition is turned off?? (is that right) or is it anything to do with my air con??

I know this may be the most bizzare question with the least detail, but has anyone heard this on their car or know what it could be before i take it to a garage and they quote me a load of ******....

Cheers folks.

Any chance of a sound clip? Could just be the turbo spooling down? Though I am not sure that would last 5 - 6 seconds. I can hear my turbo spooling down for about a second when I turn the ignition off.

Sound clip - sure. I'll try and get one tomorrow. Im pretty sure it's not the turbo though. the noise is like a decompression sound - akin to a trumpet.

You'll hear tomorrow anyway. :-)

Had mine a week and noticed this, just put it down to everything shutting down.

Interesting one. I have heard the vacuum box can make a funny noise, though I am not sure what it means if it does. That's the smallish black box at the back left under the bonnet, with several small black hoses coming from it. Just above the coolant reservoir. Maybe it's that?

Interesting one. I have heard the vacuum box can make a funny noise, though I am not sure what it means if it does. That's the smallish black box at the back left under the bonnet, with several small black hoses coming from it. Just above the coolant reservoir. Maybe it's that?

Interestingly... Thats exactly where the noise is coming from! When trying to get a sound clip of said noise, i opened the bonnet and turned the engine off. The engine settles and goes quiet but then the 'vacuum box' starts making the noise with quite a heavy vibration. So who knows what a vacuum box does?

probably flux capacitor, if ya dont keep junk in ya trunk....

Interestingly... Thats exactly where the noise is coming from! When trying to get a sound clip of said noise, i opened the bonnet and turned the engine off. The engine settles and goes quiet but then the 'vacuum box' starts making the noise with quite a heavy vibration. So who knows what a vacuum box does?

Cool. At least we've found out where the noise is coming from already then :-)

When fitting the SEAT strut brace, mine was knocked about and became slightly unclipped. It caused a huge loss in power, and felt like the car was going to stall. Very rough. I think it controls the turbo actuator and EGR at least? Maybe even just try unclipping it and clipping it back on again?

It's normal, the vacuum box holds the ASV valve shut to ensure the engine doesn't run on (ASV) cuts off all air into the inlet manifold. The buzz is due to the depleting vacuum, as the vacuum pump is also part of the fuel pump (tandem pump). That pump is camshaft driven, so when the engine stops, so does the vacuum pump. However if the buzz gets really loud, the vacuum control box needs replacing.

It's normal, the vacuum box holds the ASV valve shut to ensure the engine doesn't run on (ASV) cuts off all air into the inlet manifold. The buzz is due to the depleting vacuum, as the vacuum pump is also part of the fuel pump (tandem pump). That pump is camshaft driven, so when the engine stops, so does the vacuum pump. However if the buzz gets really loud, the vacuum control box needs replacing.

Ah nice one for that description. I think I'll start looking for one because it is loud and feels like it's getting louder. And when I turn off my ignition but the engine ticks over a couple of times more, does that sound like a symptom of the unit going? I also always press the clutch pedal down when turning off - will that matter?