Strange sound like tyre deflating or release of air?

[philsuarez]

Strange thing happened when I pulled up at Hotel car park in my 2018 model year XC90 Momentum. I was operating the electric tail gate when I heard a very loud sound like a tyre deflating under pressure or the release of compressed air. Nothing is showing as a fault on car systems. Any ideas would be greatly appreciated. I was thinking maybe something to do with the gas struts of tailgate or the power pulse tech.

[ulstrup]

no worries, is just the easy entry set up that lower the car.

[nu11eaf]

Originally Posted by philsuarez

Strange thing happened when I pulled up at Hotel car park in my 2018 model year XC90 Momentum. I was operating the electric tail gate when I heard a very loud sound like a tyre deflating under pressure or the release of compressed air. Nothing is showing as a fault on car systems. Any ideas would be greatly appreciated. I was thinking maybe something to do with the gas struts of tailgate or the power pulse tech.

Where was the sound coming from the engine bay or the rear of the car. Do you have air suspension.?.

P.S, easy entry suspension lowering is more like a creeking sound not a hissing noise.

[familymangreg]

Originally Posted by philsuarez

Strange thing happened when I pulled up at Hotel car park in my 2018 model year XC90 Momentum. I was operating the electric tail gate when I heard a very loud sound like a tyre deflating under pressure or the release of compressed air. Nothing is showing as a fault on car systems. Any ideas would be greatly appreciated. I was thinking maybe something to do with the gas struts of tailgate or the power pulse tech.

Now, this is interesting... On Sunday afternoon we pulled up into a parking area, and my wife put the car in park, she then put the car back into drive and rolled forwards a little further, and suddenly we heard a loud pop/bang and a ****shhh type sound, just as if we'd rolled over something and completely blown a tyre.

I got out of the car expecting to see a tyre completely flat, but all looked and felt absolutely fine and the car looked to be sat correctly on the air suspension.

I started the car again and immediately listened for any abnormal noise, and in particular the power pulse compressor, as I wondered if a pressure hose had blown, but nothing, all was normal. There wasn't anything on the ground either which we could have run over.

I opened the boot and was able to use the button to lower the suspension without issue.

We left the car for a few hours and then drove home on a mix of lanes and faster A roads for approx 1 hour and everything was absolutely fine, no issues with the car since.

The only other point, which I'm pretty sure won't be related is my wife reported the fan screaming loud when she parked the car the other morning, which I'm assuming must have been a DPF regeneration.

I've been following every post in this forum since around March 2016, and never seen any mention of a similar issue. Hence my surprise when I saw this post, odd!

:wq

[nu11eaf]

I wonder if there is a pressure relief valve on the air tank reservoirs. They may have over pressured and relief valve lifted to relieve excess pressure. I would think that being a pressure vessel they will have a safety relief system.

[familymangreg]

Originally Posted by nu11eaf

I wonder if there is a pressure relief valve on the air tank reservoirs. They may have over pressured and relief valve lifted to relieve excess pressure. I would think that being a pressure vessel they will have a safety relief system.

I agree, and in my head I'd put it down to either some form of pressure release valve, whether that be connected to the powerpulse unit or air suspension I don't know, or something outside of the car which just happened to sound very close, like a bird or pest scarer (but unlikely, as it really did sound like it came from the car).

:wq

[gmk666]

How weird. I had exactly this happen to mine on Saturday. I've owned the car 9 months, and this was the first time it's done it. I've got air suspension and was beginning to think it had sprung a leak, but the car seems fine.

[familymangreg]

Originally Posted by gmk666

How weird. I had exactly this happen to mine on Saturday. I've owned the car 9 months, and this was the first time it's done it. I've got air suspension and was beginning to think it had sprung a leak, but the car seems fine.

Wow, three instances of something that has never been mentioned before in the space of a few days. I can’t think of any reason for this other than Pure coincidence.

Software on our car was last updated in mid January.

:wq

[Tresco85]

We have just drove from the Lake District to Birmingham and when we were coming down the M6 we had a very loud bang and it sounded like air coming out, was expecting to see the warning coming on to say we had a flat but nothing and everything was ok, must admit that I forgot to look at the rear when we got to the travel lodge so hopefully all will be ok in the morning. This was on a XC60 not 90.

[gmk666]

Looks like I spoke too soon. The car has just dropped to its lowest setting, the ride is rock hard and this message has just appeared. Waiting for dealer to get back to me to book it in...