Strange noise

[Arnar]

Hi,

I´m posting this for my father who is having an issue with his Phev, I think its about 2years old.
Recently it started making a really strange noise, like a rumble which can be heard at low speed.
It's not the acoustic vehicle alerting system (AVAS), that one is switched off with the button.
Below are links to 2 videos he took from the car.
As heard is doesn't seem to be related to the drivetrain (engine speed) as the frequency is always the same, so more like from a motor/pump or something which runs at constant speed.

Any ideas what it could be ?

regards,
Arnar

https://youtu.be/yYlTYww8Jfg
https://youtu.be/s6_IxRcUQEU

 

[HappyHeyoka]

Is it only happening when the vehicle is in motion? (seems so from video)

Sounds like a fan rubbing on something but it looks a bit cold there for the engine fan to be on
(and no reason for the cabin fans to start and stop?)

can you tell where in the vehicle the sound is coming from?

 

[Arnar]

It only happens when it is moving but it is very difficult to pinpoint where it comes from.
Even hard to say whether it comes from the engine bay or from underneath somewhere etc.
Perhaps he could try duck taping his phone in various locations of the car and make recordings while driving to try to figure out where the sound is loudest :roll:

 

[maby]

Is it there only when running on the engine, or is there when running in EV too?

 

[fatnat]

Is it only happening when the vehicle is in motion? (seems so from video)

Sounds like a fan rubbing on something but it looks a bit cold there for the engine fan to be on
(and no reason for the cabin fans to start and stop?)

can you tell where in the vehicle the sound is coming from?

Hi there

I had a similar issue last year and my mechanic picked it up as a rear hub issue - bearings needed to be replaced.

The noise only occurred while moving, I had assumed it was noise from the exhaust pipe but wife who sometimes rides in the rear indicated it was very noisy so I had my private mechanic have a look.

See one of my posts on this issue, and be careful if this is the case as the Mitsi mechanics stuffed the replacement hub and had to subsequently replace the entire axle, took 2 months to get parts in and fix - all under warranty.

 

[Arnar]

Unlikely to be a wheel bearing issue as the frequency and volume is not related to the wheel speed.
The sound is the same whether the car is hardly creeping forward or going faster, and also it doesn't start until 1-2sec after the car starts moving.

The latest news I got is that this seems to be related to when the car was charged.
If it was just being charged this happens every time, but when it is used after charging taking place x hours/days ago this doesn't happen.
Next step will be to get it on a lift and try to figure out where the sound is coming from.

 

[Yoran]

My idea: doesnt the battery pack include its own cooling fan? Maybe hearing fan bearings, they run after charging

 

[HappyHeyoka]

My idea: doesnt the battery pack include its own cooling fan? Maybe hearing fan bearings, they run after charging

Yes, that's going to come on and off independent of vehicle speed, but only while the car is "on"

Arnar : battery box is located roughly just behind the rear seats - in fact if Yoran's theory is correct, if you flip forward the bottom of the back seats (so you can fold them flat) but leave the back of the seats still up (ie: no sound insulation from bottom of seat) it should get noisier?

 

[anko]

Arnar : battery box is located roughly just behind the rear seats

The battery box sits underneath the front and rear seats . Definitely not behind the rear seats. See how much free space we have there And IIRC the fan is in the front of the box, but I am not 100% sure of that.

(Or were you talking about the aux battery? That does sit behind the rear seats but that doesn't come with a cooling fan)

 

[HappyHeyoka]

(Or were you talking about the aux battery? That does sit behind the rear seats but that doesn't come with a cooling fan)

no, you are right, ignore me
and from sticking my head under the car, it also looks to have rubber mounts like engine block mounts? fan would have to be _really_ loud to couple through those.

so, yeah, Arnar, ignore me :roll:

 

[marweb]

Hi.
just joined the forum. I would like to ask "arnar" if there was anything resolved about the noise in his fathers phev and if so what was it.
I have had mine for a bout 5 weeks now and have just done a 220 mile journey, charged it up overnight and went to drive it and got the same noise and fans going as well. It is being lifted to go into a garage tomorrow but I would like to find out what it is if there was a solution
I thank those in advance for any info pertaining to this matter.
marweb