Creaks and groans

Faults and Technical chat for the Kia Niro
AlanW55
Posts: 253
Joined: Sat Mar 11, 2017 4:31 pm

Post by AlanW55 »

When I am driving in very slow stop-start traffic, the car is in Drive, and forward motion is largely controlled by "feathering" the brake pedal against the strong tendency to creep forward from the electric motor. (The traffic is generally moving so slowly I hardly ever need to touch the accelerator). I find that this produces all manner of creaks and groans, presumably as the brake discs are forced through the pads. There should be no noise from brakes, whatever speed, unless they're worn or faulty.
Anyone else experiencing this? I'm thinking of taking it in to Kia where I can demonstrate the problem.
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previously UK 2017 First Edition HEV in pearlescent white, standard spec.

gimball
Posts: 50
Joined: Thu Jul 07, 2016 4:38 pm

Post by gimball »

Don't inch forward on a dual clutch transmission.
The clicks could be the robot trying to guess what the hell you want to do:
a) stop -> disengage the clutch
b) go -> engage the clutch

It would be healthier to rather come to a full stop, let the car in front to move a couple of meters then go for a bit before coming to a full stop again.

(but do take it to the service to check it could be something worth checking)
h2onorth
Posts: 174
Joined: Thu Nov 24, 2016 6:19 pm

Post by h2onorth »

Hi. At slow speed most of the slowing up is done by the regeneration system surely, not the discs? My niro 2 does not make the noises you are describing. The DCS system is designed to work in these conditions and while stationery or slow in traffic the electric motor is providing the forward power thus wear and tear is far less than any other type of system with petrol / diesel vehicle.
If you are worried about noises see your dealer.
h2onorth
AlanW55
Posts: 253
Joined: Sat Mar 11, 2017 4:31 pm

Post by AlanW55 »

I believe I've got to the bottom of the problem. I was exiting a multi-storey car park this morning, and was stopped on a down ramp, in Neutral, holding the car with the main brake pedal. As the car in front moved off, I gradually released the brake pedal and there were the creaks and groans. So it seems my pads/discs are "resonating" at very low speeds. Off to dealer next week!
Gimball, your advice re inching in a DCT is valid when the car has a conventional engine, to minimise clutch slippage. There is no clutch slippage with an electric motor that can deliver torque from zero revs and that cannot stall. I've no idea what you mean when you talk about clicks, I never mentioned clicks in my original post. Thanks, anyway.
H2onorth: I an talking about a situation in very slow moving traffic, when the electric motor is trying to creep forward and I am holding the car back with the brake. Regenerative action occurs on the overrun when the motor is not pushing, but is being pushed. Thanks, anyway.
UK 2021 Mark 1 HEV 4 in silky silver, standard spec.
previously UK 2017 First Edition HEV in pearlescent white, standard spec.
Suman
Posts: 103
Joined: Tue Apr 11, 2017 11:19 am
Location: London

Post by Suman »

Those groans happen on my car too sometimes, but I found a solution is to 'clean' the brakes by doing a fairly hard bit of braking from 30 mph on an empty road (making sure there's no one behind you first).
Kia Stinger GTS in Panthera Metallic Grey
Previously: Kia Niro First Edition in Pearlescent White, Mercedes GL 420 cdi, Lexus LS460 SE-L, Renault Laguna Initiale 2.0 dci, Lexus LS 460 SE-L, Renault Megane 1.9 dci, Toyota Supra 3.0 Turbo
Deleted User 440

Post by Deleted User 440 »

I know these "Creeks and Groans" from my Niro and I know them also from other conventional cars I had. It happens when the brakes are not fully enganged and the car is still pushed by some other force. In the Niro it is the force of the electric motor, which still tries to push the car against the half-engaged brakes. Only if the brakes are pushed beyond a certain point the electric motor is switched off and the groaning stops. In general this is no reason for concern.

However it is a situation which should be avoided if possible. So I would recommend to either push the brakes firmly enough so that there is no "groaning" or the let the electric motor creep the car without braking.
AlanW55
Posts: 253
Joined: Sat Mar 11, 2017 4:31 pm

Post by AlanW55 »

Spot on niddam99, you've grasped what I was saying perfectly. Thanks.
I didn't realise pressing the brake fully switched off the motor, this means I don't have to move into Neutral when I stop at the traffic lights. I assumed the motor was always pushing.
UK 2021 Mark 1 HEV 4 in silky silver, standard spec.
previously UK 2017 First Edition HEV in pearlescent white, standard spec.
AlanW55
Posts: 253
Joined: Sat Mar 11, 2017 4:31 pm

Post by AlanW55 »

Took it into dealership today, he concurred that it was the front disc brakes, and that Kia are aware of the issue with other Niros. Apparently they are monitoring the number of complaints and MAY act if there are enough. (This could all be a load of bovine excreta).
Any replacement discs/pads are still as original equipment, so no obvious solution. He assures me there is no danger, so I'm reasonably assuaged, although not entirely happy!
I can't see any copper grease on the calipers, wonder if they used any!
UK 2021 Mark 1 HEV 4 in silky silver, standard spec.
previously UK 2017 First Edition HEV in pearlescent white, standard spec.
Ritz
Posts: 34
Joined: Wed Apr 12, 2017 11:18 am

Post by Ritz »

My car seems to be suffering from these creaks and groans normally when i release the brakes from being at a complete stop or just as i get to a full stop and is very audible from outside the car. I was hoping that it would have settled down, but I've now just done 1000 miles and it still seems the same.
Sounds like i may need to get it checked out.
NiNiro
Posts: 14
Joined: Sun Jun 18, 2017 6:02 am

Post by NiNiro »

I would agree with others here stating that the brakes are the likely cause. It is common to hear rear brakes doing this in regular cars as the forces are less at the rear and depending on the user and or brake balance the disks/pads can gather dust and make noise.
This is more likely on vehicles with regenerative braking as the friction brakes are used much less. As suggested above, good practice to prevent this is firm braking. Also give the wheels/brake area a good hose down when washing to remove loose build up of dust.
With regard to inching forward in traffic:
If you check out the function of the Kia hybrid drive train you will find that 1st gear and clutch is always engaged at a stop - the motor applies power when brakes are released with no clutch slip. This is a very good system for preventing energy loss through clutch slip and also clutch wear. Inching forward in a pure ICE DCT drivetrain will cause excess clutch wear as to transfer torque without stalling the engine slip is required.
It would still be good practice not to inch forward (in the Niro) in a stop start fashion as the current drawn by the motor to build momentum each time will be more than if you move one or more car lengths before coming to a stop again. This would increase the available battery energy for actual driving.
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