audi q5 question

August 12, 2014 5:02 PM

yesterday morning when my wife started her brand new audi Q5 2014, it started giving out a weird sound from the rear section, sth akin to horse hoof beating on the road. she got off the car twice to check what's going on and found nothing out of ordinary. after about 40 mins, she parked at her friend's place and then she started hearing the typical sound when the tire is leaking air. she then saw one of the front tires was going flat. the whole sequence of events was a bit traumatizing for her as she is a new driver with less than a year of experience driving any kind of car, and this is a brand new Q5 with only 90 miles on it. later on after auto shop fixed the tire, the weird sound disappeared. my questions: 1. were the two events (weird sound and flat tire) related? 2. what was that sound? is it some kind of warning system by audi? 3. why didn't the tire pressure monitoring system warn her? thanks,
posted by kingfish to Travel & Transportation (8 answers total)

Well, seeing as she didn't have this sound before or after the tire incident, they're more than likely related. The sound could have been any number of things, from the car being slightly off balance and causing strain on the other tire on that side at a frequency related to a slight wobble in the car's stability. Or maybe she has some sort of stability control or traction control that was trying to compensate for a flat tire that made the noise. Really, this is a question for the dealer.

As for why the tire pressure system didn't warn her... well, that one is definitely a question for the dealer.
posted by mikeh at 5:14 PM on August 12, 2014

Did they take something out of her tire? Yes, you can get some crazy sound effects from a hard object impaled in your tire hitting the road.

Possibly she did not start losing air until she stopped moving and that's why the pressure monitor didn't do anything.
posted by Lyn Never at 5:15 PM on August 12, 2014 [1 favorite]

Rhythmic clicking sounds on the road are often a pretty good sign you have a stone stuck in your tread or something like a screw puncturing the tyre. I noticed my last puncture through hearing a noise on the road (and I then left the screw that had punctured it in until I got to a tyre shop two weeks later. Sometimes you can take a punt and get lucky.)

More than likely the fact that the car had 90 miles on it was just a coincidence.
posted by deadwax at 6:04 PM on August 12, 2014

Could have been a section of the tread peeled off, and was either hitting the inside of the guard, or the road, and making that sound. Check inside the guard for any damage, although the shop should have done that.

When you say fixed the tyre, did they repair it, or replace it? What did the shop say about the tyre? Is the tyre still available for inspection? Could be, if it was a tyre failure (rather than a puncture), there is a case for claiming warranty.
posted by GeeEmm at 6:28 PM on August 12, 2014

when my wife started her brand new audi Q5 2014, it started giving out a weird sound from the rear section, sth akin to horse hoof beating on the road.

This is not at all clear. When she started the car (as in started the engine)? Or When she started driving.

If it is when she is driving this is simply a puncture. No big deal at all. The 'hooves' noise is the thing that punctured the tyre still stuck in the tyre and hitting the road as the tyre rotates. When the piece fell out the air came out and the tyre deflated. Perfectly usual occurrence of a relatively unusual (in terms of frequency of occurrence) problem with driving a car.

3: This is the only odd part of this question. Likely the loss of air pressure wasn't enough to trigger the sensor. She may have (by chance) heard the leak before the pressure dropped low enough to trigger the warning. It needs to be a reasonably large difference in pressure to get the system to trigger.
posted by Brockles at 7:35 PM on August 12, 2014

Is it possible the tire pressure monitoring system (TPMS) sensor itself was broken and loose from the valve stem? This might explain both why the TPMS didn't alert her (the sensor wasn't talking to it) and why she heard a noise (the TPMS sensor was bouncing around inside the tire, making the noise). I don't specifically know how the sensor attaches on a Q5, but on my Fusion, it's a small bit of plastic and metal through which the valve stem threads (and a new one costs about 3 bucks).

I know she thought the sound came from the rear, but due to inexperience and these things having a way of playing tricks on a person, not to mention the fact that fixing the front tire also fixed the sound, maybe it was really coming from the front tire.

I'd ask the auto shop to describe exactly the problem and their fix for it.
posted by axiom at 9:19 PM on August 12, 2014

I suggest you ask this very question over at the Audizine forums. There's some pretty Audi-knowledgeable people over there.
posted by Diag at 4:50 AM on August 13, 2014

Response by poster: thanks all, this is very helpful...
posted by kingfish at 5:06 PM on August 13, 2014