2009 XC70 T6 AWD - Whining Noise from TCV @ Unlock

rod850 · Post by **rod850** » 06 Mar 2014, 02:31

So I finally got my wife into a Volvo!!!
We brought home a used 2009 XC70 T6 AWD a couple of days ago.
I went down to the garage last night to put in an ice scraper for her and noticed a whining noise coming from the general vicinity of the vacuum pump when I unlocked the car (engine is not running). The noise stopped after a couple of minutes but I want to make sure that nothing is wrong or if something is, I know what to tell the dealership to look at.
The only repair they did before putting it on the lot was to replace the vacuum pump so my main concern is that something is wrong with the install or the part or something related that should have also been replaced.
Any help would do a lot to ease my mind that my prego wife isn't driving a ticking time bomb.
This video shows what is going on:

Thanks!

rod850 · Post by **rod850** » 07 Mar 2014, 11:58

Post by **VCA** » 07 Mar 2014, 15:00

That's a normal sound. My 2008 S80 makes this sound, as does a 2010 V70 that I've driven. The vacuum pump is engine-driven, so it's not that (they tend to leak oil, mine was changed a year ago for that). In the vicinity of where you videoed is the ABS pump (which I believe does a self test when the car is powered up), and I believe this to be the source of the noise, though I haven't investigated it thoroughly since it's a sound I've heard on two cars on the same platform. Happy motoring!

Post by **jimmy57** » 07 Mar 2014, 19:27

Turbo control valve is cycled when the network comes up and ECM is active. Normal noise.

Post by **VCA** » 07 Mar 2014, 20:09

jimmy57 wrote:Turbo control valve is cycled when the network comes up and ECM is active. Normal noise.

Ah-ha! I forgot the common denominator! Both cars I heard it in were T6s...didn't even think of the turbo's electrically-activated bypass valve, because, of course, it was vacuum-actuated on the S/V/C70 family...

rod850 · Post by **rod850** » 08 Mar 2014, 10:10

So it sounds like the noise is from the TCV.
Is it always that loud?
This post says that around 60k they start to go:

https://www.matthewsvolvosite.com/forums ... =1&t=48871

Our car is @ 63k so does the noise get louder as they start to go?
Sorry for all the questions just want to make sure the dealership knows of any problems ASAP.
Thanks

Post by **VCA** » 11 Mar 2014, 10:28

The TCV is a different part # than the older cars, I would expect the newer part to be longer wearing (Volvo has a good record of fixing the weak spots in later iterations of their cars). My S80 has 82k on the clock with no signs of it going bad, while the friend's V70 has, I think, around 160k on it.

Post by **jimmy57** » 11 Mar 2014, 13:08

I was referring to the tcv and yes they are loud enough to hear if you listen or if car is in quiet area. If it has been disturbed by repairs or service then it will louder than it used to be. Pull engine cover and with it buzzing see if the noise level changes if you move it.

rod850 · Post by **rod850** » 12 Mar 2014, 08:03

Well I went down last night to look under the engine cover and the noise is barely noticeable.
I've been telling my wife to let the car idle for a minute or two after she starts it and before she turns it off so the oil can circulate to the turbo, I don't know if that has made the difference or if maybe the weather warming up a bit did something, but the noise is exponentially quieter.
I'm going to keep my ear on it, but I'm thinking I can move my attentions else where.
Thanks for all the input.

Post by **abscate** » 04 Jun 2014, 06:20

You can get better compliance if you mark off 30 seconds from home and ask SWMBO to coast down from there into the driveway with revs under 2000 rpm.

No one likes to sit in the driveway, unless you bring her a martini first.