Not sure if I have a problem or not - whistling sound under acceleration

[chrishamer]

Hi All,

I have a 2012 A4 B8.5 1.8 TFSI 170 and have noticed that under acceleration (1700-3500) there is low whistling sound coming from the bonnet.

It seems to only be under drive rather than revving whilst stationary but I don't think it's non engine related as pushing in the clutch stops it and at the same speed changing down a gear means you can't hear it either (i.e accelerating in 2nd to 3500 rpm you'll hear it and then if you change into 4th and are at 1200rpm whilst continuing to accelerate you won't hear it till 1500/1700 or so).

The car is still under the approved warranty so I'm tempted to take it in and get Walton Audi to look at it but was wondering if any of you have any ideas?

It's just odd as the car wasn't doing it a month or two ago... There's been no loss of power, or any drive issues.

Any help appreciated.

Chris

[warp_speed]

Hi All,

I have a 2012 A4 B8.5 1.8 TFSI 170 and have noticed that under acceleration (1700-3500) there is low whistling sound coming from the bonnet.

It seems to only be under drive rather than revving whilst stationary but I don't think it's non engine related as pushing in the clutch stops it and at the same speed changing down a gear means you can't hear it either (i.e accelerating in 2nd to 3500 rpm you'll hear it and then if you change into 4th and are at 1200rpm whilst continuing to accelerate you won't hear it till 1500/1700 or so).

The car is still under the approved warranty so I'm tempted to take it in and get Walton Audi to look at it but was wondering if any of you have any ideas?

It's just odd as the car wasn't doing it a month or two ago... There's been no loss of power, or any drive issues.

Any help appreciated.

Chris

Could it not be the Turbo spooling, when decelerating or revving in idle the turbo won't spool as the bypass valve will kick in, it will only start applying pressure (spooling) when you're in a certain rev range and in gear driving the car. My 2007 2.0T used to make a whistling sound but only when you reached passed 2k, in gear and driving the car. I'm assuming the ECU knows when the car needs the turbo or not.

[chrishamer]

Unfortunately I don't think so, the turbo makes a different sound, this seems quite a bit louder and only started in the last month.

This being said, I'm now questioning whether I'm right or not.

My other suspicion is the air filter so I might get it changed just to see if it makes a difference.

The only reason I'm worried is that I'm now 7000 miles since I bought the car and I'm driving to Austria in April - so that'd be a 2,500 trip and I don't want any issues coming up during the drive.

[warp_speed]

Unfortunately I don't think so, the turbo makes a different sound, this seems quite a bit louder and only started in the last month.

This being said, I'm now questioning whether I'm right or not.

My other suspicion is the air filter so I might get it changed just to see if it makes a difference.

The only reason I'm worried is that I'm now 7000 miles since I bought the car and I'm driving to Austria in April - so that'd be a 2,500 trip and I don't want any issues coming up during the drive.

Check for air leaks in any of the breather lines or as you suggested the air lines coming from the air filter. They kind of make a consistent noise that doesn't alter with speed, its possible a valve opens up during the rev range.

I know what you mean, I have an inconsistent wheel wobble that my Audi dealer can't find what the issue is and I'm planning on going to Germany in the summer, don't need issue either.

Best of luck