TDI owners - droning/humming noise on light acceleration?
10-28-2014, 04:24 PM
#11
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I have been noticing a slight humming / droning noise on light acceleration in the past month on my 2014 Q5 TDI with roughly 15k miles on it. I haven't really noticed this before so I'm not sure if it was always there - I think it was not.
The noise is not always there making it hard to track. However, when it is there, it only happens when accelerating lightly and it is more noticeable on the highway when the cabin is quiet. Downshifting does not change the tone of the noise at all, so it doesn't appear to be RPM related. It is also very hard to place but it seems to be coming from the rear (possibly driver rear).
The dealer stated that this is normal and it is the Adblue pump but I'm not sure this is the correct explanation - the noise sounds more like a lower pitch bearing type of noise than a higher pitched whine typical to pumps.
Do any of you TDI guys have the same noise?
The noise is not always there making it hard to track. However, when it is there, it only happens when accelerating lightly and it is more noticeable on the highway when the cabin is quiet. Downshifting does not change the tone of the noise at all, so it doesn't appear to be RPM related. It is also very hard to place but it seems to be coming from the rear (possibly driver rear).
The dealer stated that this is normal and it is the Adblue pump but I'm not sure this is the correct explanation - the noise sounds more like a lower pitch bearing type of noise than a higher pitched whine typical to pumps.
Do any of you TDI guys have the same noise?
10-29-2014, 12:27 AM
#12
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If it's a 3.0 TDI and the noise is noticeable at around 1.050-1.100 rpm... then you've got a serious problem. We're haveing this issuen in Europe and Audi doesn't have a solution.
Sorry!
Sorry!
11-06-2014, 02:21 AM
#13
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Hi:
Was about to start a new post when I found this thread. Our 3.0 TDI Q5 (now 5 months old, 8000 km) has a similar or the same noise. It's most noticeable at very light/trailing throttle at suburban speeds, and appears to me to be coming from the rear. Any increase/decrease in throttle opening seems to make it disappear, but there may be some noise at higher speeds as well although much harder to discern.
When I mentioned it to my service supervisor at the 3000 km service he thought tyres, but I can't buy this! It is very predictable and can be produced at will, so I don't think it is a pump or other Audi "thing" special to this car. If I had to put money on it, I would say excess backlash in a diff or CV joint, probably the rear as that's where it seems to come from as mentioned, or possibly a wheel bearing as a much less likely option; but sounds can be very hard to track down as members will know full well.
Will be interested to hear others' comments! First post on this forum so hope I haven't missed anything important I should add.
Was about to start a new post when I found this thread. Our 3.0 TDI Q5 (now 5 months old, 8000 km) has a similar or the same noise. It's most noticeable at very light/trailing throttle at suburban speeds, and appears to me to be coming from the rear. Any increase/decrease in throttle opening seems to make it disappear, but there may be some noise at higher speeds as well although much harder to discern.
When I mentioned it to my service supervisor at the 3000 km service he thought tyres, but I can't buy this! It is very predictable and can be produced at will, so I don't think it is a pump or other Audi "thing" special to this car. If I had to put money on it, I would say excess backlash in a diff or CV joint, probably the rear as that's where it seems to come from as mentioned, or possibly a wheel bearing as a much less likely option; but sounds can be very hard to track down as members will know full well.
Will be interested to hear others' comments! First post on this forum so hope I haven't missed anything important I should add.
11-07-2014, 07:06 AM
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Hi:
Was about to start a new post when I found this thread. Our 3.0 TDI Q5 (now 5 months old, 8000 km) has a similar or the same noise. It's most noticeable at very light/trailing throttle at suburban speeds, and appears to me to be coming from the rear. Any increase/decrease in throttle opening seems to make it disappear, but there may be some noise at higher speeds as well although much harder to discern.
When I mentioned it to my service supervisor at the 3000 km service he thought tyres, but I can't buy this! It is very predictable and can be produced at will, so I don't think it is a pump or other Audi "thing" special to this car. If I had to put money on it, I would say excess backlash in a diff or CV joint, probably the rear as that's where it seems to come from as mentioned, or possibly a wheel bearing as a much less likely option; but sounds can be very hard to track down as members will know full well.
Will be interested to hear others' comments! First post on this forum so hope I haven't missed anything important I should add.
Was about to start a new post when I found this thread. Our 3.0 TDI Q5 (now 5 months old, 8000 km) has a similar or the same noise. It's most noticeable at very light/trailing throttle at suburban speeds, and appears to me to be coming from the rear. Any increase/decrease in throttle opening seems to make it disappear, but there may be some noise at higher speeds as well although much harder to discern.
When I mentioned it to my service supervisor at the 3000 km service he thought tyres, but I can't buy this! It is very predictable and can be produced at will, so I don't think it is a pump or other Audi "thing" special to this car. If I had to put money on it, I would say excess backlash in a diff or CV joint, probably the rear as that's where it seems to come from as mentioned, or possibly a wheel bearing as a much less likely option; but sounds can be very hard to track down as members will know full well.
Will be interested to hear others' comments! First post on this forum so hope I haven't missed anything important I should add.
11-13-2014, 04:17 PM
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Will be interested to hear how you persuaded the dealer to do the work? And a longer-term report on the success or otherwise of the c/o diff in eliminating the noise.
11-14-2014, 01:58 AM
#17
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After replacing the transmission and centre diff, they've isolated it to the rear diff. Should have it back today. 4 trips and 6 weeks in the shop...
11-18-2014, 03:54 AM
#18
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Rear diff appears to have been the issue for me - noise is gone.
11-18-2014, 03:56 AM
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That's probably the correct fix this time - did it work out for you? I got a bit luckier - they got mine right the first time, although it took 1 week in the shop since they had to get the part in stock from Canada (so it's probably not a common problem so far!)
11-24-2014, 02:57 AM
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Will be speaking with my dealer tomorrow about my noise, so thanks for the updates. I'm now thinking that there is a humming at normal speeds and throttle positions as well as under very light loading; perhaps I'm getting more sensitised to noise but I don't think that's it, as the original noise seems to be louder as well.