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Discussion Starter #1
Bought a 2012 3 years ago ( thanks to 4wdmd, Fibber2 and Sandroad for post reply way back then). For about a month now I've been hearing a squeek or chirp when driving between about 40 to 60 mph. It only lasts for a second and only happens when I let off the throttle and get back into it. If I ease very slowly or very quickly back into the throttle it does not seem to happen or I just can't hear it. But with my normal throttle application it will do it repeatedly. A week ago I replaced the belt, tensioner and idler with Gates products. It went away for a day or so and is back. I did not clean off or de-glaze the pulleys. In a heavy rain it does not seem to do it. So it's happening at very low engine loads at relatively higher speeds. This car has 83,000 miles on it and has not been abused, at least for the 20,000 miles I've had it.

My thoughts are that it is still the belt and that I need to clean the pulleys and de-glaze them and also make sure the new tensioner is working smoothly.

If that does not work then I think it has to be the CVT, which I thought I saw had a warranty extension done that would include this car. Though I really hope that's not it
as I really like this car.

I've read the posts I can find about the chirp and would appreciate any feedback.

Thanks.

Roger
 

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2008 Outback Wagon 2.5i limited
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On my 08, I have been getting a similar noise for a few years now, nothing seems to be getting worse or failing. I tend to think it might be a vacuum leak related to the throttle, but haven’t looked into it in depth. No throttle cable, I believe it’s called DBW. I might be wrong, but I assumed it must involve a diaphragm yo apply vacuum when you want to accelerate, via the ECU. I’m sure one of the pros like @cardoc might be able to shed light on how it works. Like you said, as soon as you let off the throttle, it goes away.
 

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2008 Outback Wagon 2.5i limited
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I looked into the way the DBW function works and apparently it does not involve a vacuum diaphragm. It seems to have a DC motor that operates the throttle plate. That being said, if your noise is similar to mine, it must be something else. For a while, I thought maybe the A/C system was low on refrigerant. I added some to bring up to okay and it seemed better for a while. I later realized that the noise still occurs even though the HVAC system is completely off. Still a mystery to me!
 

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Discussion Starter #4
Yesterday I took the belt and tensioner off and cleaned all the pulleys with brake clean and a brush. I bolted the tensioner to my bench and rotated it through it's range of motion and it felt a bit tight to me. I lubed it with superlube then a little mobil 1.
It smoothed out and is comparable to the old one I still have. The new Gates belt did not look good. There were sections at the bottom of the grooves were rubber was stuck to the belt. I did not look at it before I put it on so I don't know if this was from the belt slipping and causing melted sections or what. It did not want to come off easily so I just replaced it with a new Continental belt. I drove it to work today and no noise, time will tell if that was it.
 

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2010 UK Spec Outback CVT 2.5 litre Petrol
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Hello - if the chirping returns then check if your car has an overrun pulley on the alternator (I think they all do but mine's not a US spec and maybe you guys get something different?).
These pulleys can wear with age and you end up with (effectively) a solid pulley with no spring/clutch/overrun effect that then allows the drive belt to skip over the pulley giving a good 'chirp' sound.
 

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Discussion Starter #6
Graeme, Thanks for the suggestion. The sound is back so I'll check the pulley.
 

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Discussion Starter #7
I just checked and it has a standard pulley. At this point I don't know what else it could be besides the CVT as it happens at such a specific road speed and engine speed with very little load on the engine or CVT.
 

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Discussion Starter #8
I stopped by the dealer and mine is covered by the warranty extension and will be going in for evaluation next week. I'll post an update after.
 

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Discussion Starter #9
Dealer test drove it today and said they could not duplicate the sound. I'm letting them keep it longer to try again. It does it often enough to me that they will hear it sooner or later.
 

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Discussion Starter #10
Dealer was able to duplicate noise today and has ordered a CVT for it. It was diagnosed as the CVT belt slipping.
 
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