Team-BHP - Hissing sound in my VW Vento TSI

Hello everyone,

I would like to state one of my very recent experience with you and take your suggestions.

I drive a Vento TSI, Feb'2016 model.

Last Sunday, I was on my way back from Jaisalmer to Delhi. After I drove off some 650 odd kms, I noticed some sound (very similar to gas leakage) coming off intermittently from somewhere beneath the glove-box. I was driving non-stop for over 5 hours by then and thought of taking a quick tea break. While on break, I just opened the engine hood for 15 minutes and restarted my journey back to Delhi again. The sound occurred for another 10 minutes (with intermittent intervals) before went off completely.

I must mention here that the sound was coming with my push on the accelerator; when the accelerator was idle, there was absolutely no sound.

Since Sunday, I've not driven her again and so not sure if it would recur again. But in case it does, do I need to visit service station straight or there is some DIY you guys would like me to try.

Many thanks in advance.

This sound is also very audible on the TDI Vento's.

It used to drive me crazy, this hissing sound on acceleration, and I asked the service people about it one day, thinking it was an issue with the car.

I was told that it has something to do with the AC, but then why only when the car accelerates?

I personally think it is turbo whistle, but why it should emanate from that area is beyond me.

If it is coming only when you have your foot on the accelerator pedal, it is just a case of the turbo whine.... Dont worry about it. Thankfully you have warranty for the foreseeable future!

Most new turbos have a noise like that. They should quieten down over time.

Dodge: Am not sure, may probably be. Have you taken any advice from your dealer/SA regarding this?

Pillianp: In my case, this is a recent occurrence. I have driven her 3,800 km in one month, with over 3,000 km on highways, and the sound started post 3,000km, not before that. What did you SA told you regarding the rectification measure?

NikhilB2008: Thank you, I just hope it does! What you suggest: should I take her for inspection once or just wait and watch?

Gannu_1: Sure, will try and update you. Many thanks.

Mod Note: Please use multi-quote feature instead of creating multiple posts

For me the issue was sporadic in nature. It would appear and disappear at random.

The SA said that they had cleaned some AC pipe and the sound would not recur, but it started again shortly thereafter and persisted sporadically till I sold the car last month.

It had no noticeable effect on performance, just that it was very intrusive in an otherwise quiet internal environment.

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Kindly ensure that you proof-read your posts prior to submission. Also, it would be a good idea to use a spell-checker.

In my 2012 polo TDI also the same sound is present. I too think it's something related to the AC. I would suggest you to switch off the AC and try to listen. If it's there, it's almost sure that it's something related to the HVAC system.

Quote:

Originally Posted by sajusherief (Post 3941955)

I too tend to think that it's to do with the AC, as I remember now I switched off the AC for sometime and then the sound disappeared. Did you happen to take any advice from your SA regarding this?

One of my friend who owns a Polo 1.5 TDI had similar issues of hissing sound during acceleration and AC being in recirculation mode. We headed to VW Mysore and after an entire day of inspection and testing, it turned out to be an issue with AC where the flaps wasn't functioning properly when turning the re-circulation mode on and off. It was fixed and the noise was reduced considerably. You may also want to check with SC on the same

Quote:

Originally Posted by vin_b (Post 3942003)

Thank you for your inputs - it definitely provides me a starting point. Also, just for my understanding, was your friend facing this issue only when the AC was on recirculation mode?

Quote:

Originally Posted by NiladriM (Post 3942072)

Thank you for your inputs - it definitely provides me a starting point. Also, just for my understanding, was your friend facing this issue only when the AC was on recirculation mode?

Yes, the problem was noticed only when AC was on and the noise increases if it is switched to recirculation mode. But, in general there is a faint hissing sound which I believe is from the turbo.

Quote:

Originally Posted by vin_b (Post 3942003)

Quote:

Originally Posted by vin_b (Post 3942081)

Yes, the problem was noticed only when AC was on and the noise increases if it is switched to recirculation mode. But, in general there is a faint hissing sound which I believe is from the turbo.

Sure, noted. Will speak with my SA at the earliest opportunity and update this thread. Thank you.