Subaru Forester II (2002 - ) - 07 2.0 Strange noise when slowing (intermittently) | Technical matters | Back Room Forum

Thu 14 May 2009 09:24

07 2.0 Strange noise when slowing (intermittently) - Yachtmaster

This is difficult to describe.

It doesn't always do it and only does after a while, when slowing, or having slowed. I haven't detected it during braking yet but it does make the noise when not breaking. The noise is quiet and COULD be something rubbing (friction). It is a single, medium high pitched tone whine that lasts between one and several seconds and is not the powered steering as it does it whilst on a straight, I assume. It appears not to be serious, but I am curious and it is annoying. Your thoughts are appreciated.

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Thu 14 May 2009 22:14

07 2.0 Strange noise when slowing (intermittently) - Dave_TD

Resonance from a piece of trim, bumper, exhaust heat shield etc?

Is it linked to road speed or linked to engine speed? (ie does it appear only within a certain range of revs?) My car's exhaust heat shield buzzes for 500rpm either side of 2900rpm, I know its a lot older than yours but the idea's worth suggesting.

Dave TD.

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Fri 15 May 2009 09:52

07 2.0 Strange noise when slowing (intermittently) - Yachtmaster

I had heat shield vibrations on my previous Forester. This is different and difficult to describe, which doesn't help here. It is not linked to speed or engine revolutions. I have an uninformed thought that it could possibly be the fuel pump. Is that possible?

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Sat 16 May 2009 01:51

07 2.0 Strange noise when slowing (intermittently) - Dave_TD

Anything's possible. Taking all suitable precautions (such as using your own private, infinitely long, wide and deserted airfield), try and get it to make the noise then turn the engine off and see if it goes away. That should rule in/out any drivetrain related sources.

buzzes for 500rpm either side of 2900rpm

Sorry, I meant 50rpm either side. It's a very fleeting thing, although still annoying.

Dave TD

Edited by Dave_TD {P} on 16/05/2009 at 01:52

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Sat 16 May 2009 10:24

07 2.0 Strange noise when slowing (intermittently) - Peter D

If you open the throttle briefly does it suppress the noise. If so this could be a vacuum leak as when you take your foot off the vacuum is at it's highest. Regards Peter

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Tue 19 May 2009 20:08

07 2.0 Strange noise when slowing (intermittently) - Yachtmaster

If you open the throttle briefly does it suppress the noise. If so this could

be a vacuum leak as when you take your foot off the vacuum is at

it's highest. Regards Peter

What is a vacuum leak?

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Tue 19 May 2009 20:21

07 2.0 Strange noise when slowing (intermittently) - Peter D

Could you just answer the question. What part of vacuum leak do you not understand. Regards Peter

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Wed 20 May 2009 09:15

07 2.0 Strange noise when slowing (intermittently) - Yachtmaster

Could you just answer the question. What part of vacuum leak do you not understand.

Regards Peter

Yes I think it does stop the noise when I use the throttle again, however it occurs too infrequently to make a reasonable assessment. For the while, it seams to have disappeared , at least temporarily.

I do not know what a vacuum leak is. Please explain.

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Wed 20 May 2009 10:49

07 2.0 Strange noise when slowing (intermittently) - Dynamic Dave

I do not know what a vacuum leak is. Please explain.

Think of it as a vessel with all the air evacuated. But over a period of time the air finds its way back in.

The reverse of a balloon that has a leak if you like.

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Wed 20 May 2009 11:28

07 2.0 Strange noise when slowing (intermittently) - Peter D

Your braking system and some control valves use the vacuum generated by the inlet manifold, it may be you have a leak somewhere and the vacuum is at it's highest on the over-run with your foot off the throttle. applying the throttle again reduces this vacuum and the whistling noise stops again. As this is an 07 model is it still under warrantee. Regards Peter

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Wed 20 May 2009 18:52

07 2.0 Strange noise when slowing (intermittently) - nick

Climate control/aircon systems can sometimes give rise to some strange sighing noises.

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Wed 20 May 2009 18:54

07 2.0 Strange noise when slowing (intermittently) - doctorchris

Is this noise not your passenger sighing in relief that you have finally slowed down!