MK4 Yaris Hybrid occasionally making loud pump noises?

[baxuz]

Haven't managed to record this but I'll try to explain.

When driving uphill on steep roads at low RPMs and sometimes even when idling there is this loud noise that I don't think is the engine noise, as it sounds more like a loud fridge compressor or a petrol generator. Seems to overlap the regular engine noise and it's a bit higher pitched and sounds... Hmmm. A lot less refined, let's put it like that.

What's interesting is that during idling, it says it's charging the Battery, but the fuel consumption gauge is at zero when it kicks in.

The AC has no impact on the noise.

Does anyone have any ideas if this is something to worry about?

[Cyker]

The engine seems to get a lot rougher when running while stationary so it could be that? The Mk4 has a lot of electrically driven pumps so it could also be the fan, AC compressor, oil pump, MG1 etc. but hard to guess more without hearing/seeing.

I reckon it's just the engine tho' - I've mentioned in other threads that when the car is stationary or moving super slowly, and the engine kicks in, it is really obnoxiously loud and vibraty and diesel-like and you can feel the vibration through the wheel and pedals, but as soon as you start rolling it quietens down to its normal self.

Really weird but apparently is normal behaviour??

I read somewhere that unlike the M15A-FKS, the M15A-FXE in the hybrid doesn't have any balancer shafts for the 3-cylinder, but has the counterweight in MG1 so I am speculating that when that spins it smooths the engine out, but when it's stationary it can't and you get this nasty low-rpm diesel-like dakka??

 

[preperationlaunch]

There's a brake booster vacuum pump that runs too, that's powered electrically as there's no guarantee of engine vacuum at any point. It'd be a bit useless if you had to start the engine to be able to brake.

[Bernard Foy]

Well mine does something similar, don’t think it’s anything to worry about 

[AlJ]

37 minutes ago, preperationlaunch said:

There's a brake booster vacuum pump that runs too, that's powered electrically as there's no guarantee of engine vacuum at any point. It'd be a bit useless if you had to start the engine to be able to brake.

That's exactly what I was thinking. It can start at any time to ensure that the brakes are ready when needed These hybrids are full of amazing technologies, so much so that a lot of traditional thinking on what a car 'does' don't apply. I'm getting quite used to its various sounds now but the trouble is if anything was wrong, I'd think, "Oh, it's just the car doing its thing!". 

[baxuz]

So, nothing to worry about it seems. Thanks!

[Sooty]

Does the Yaris Hybrid have a traction Battery cooling fan and vent like the Prius has?

With the lately warmer weather I wonder if it that fan that can be heard, especially if anything is covering the fan vent / grille.

[Bernard Foy]

8 minutes ago, Sooty said:

Does the Yaris Hybrid have a traction battery cooling fan and vent like the Prius has?

With the lately warmer weather I wonder if it that fan that can be heard, especially if anything is covering the fan vent / grille.

Yes it does, and it can’t do any harm to check it out. Usually access under nearside rear passenger seat there is an access panel. Ensure that it not obstructed by anything in the footwell and that the filter is clean.

[TonyHSD]

Best to record the noises and sounds but most likely are normal. As others said already full of technology that differs from standard petrol or diesel cars. 👍

[Georgey Porgey]

We have the same issue with our 22 plate yaris.

 

 

[Mikw]

On 3/30/2022 at 8:11 PM, baxuz said:

Haven't managed to record this but I'll try to explain.

When driving uphill on steep roads at low RPMs and sometimes even when idling there is this loud noise that I don't think is the engine noise, as it sounds more like a loud fridge compressor or a petrol generator. Seems to overlap the regular engine noise and it's a bit higher pitched and sounds... Hmmm. A lot less refined, let's put it like that.

What's interesting is that during idling, it says it's charging the battery, but the fuel consumption gauge is at zero when it kicks in.

The AC has no impact on the noise.

Does anyone have any ideas if this is something to worry about?

Yeah, i get that with mine, it seems to be louder on first start up or if the traction Battery is a bit low. when it does it the Battery bars seem to go up quicker.

[TonyHSD]

3 hours ago, Georgey Porgey said:

We have the same issue with our 22 plate yaris.

 

There is no issues and the noises are normal and typical for the hybrid. If anything goes wrong with the car you will get a warning message on the dashboard, until then just enjoy your car and don’t worry about it 👍

[baxuz]

11 hours ago, Georgey Porgey said:

We have the same issue with our 22 plate yaris.

 

Yep! That's the noise!

 

[Cyker]

Yeah that's just the engine I think - Mine sounds like that when the engine is running while the car isn't moving. I don't get why it's so dieselly in that situation, as when the car is moving, even at like 1 mph, the ICE is much more refined (Well, as refined as an unbalanced 3-pot can be  )

I've was trying to catch the sound where the engine is already running before I stop so you can hear the switchover, but it's been surprisingly hard as usually when I stop the engine immediately cuts out, and one time I did catch it you can't really hear the change in the playback as the crappy mic doesn't pick it up very well; Doesn't help that there's so much noise from the wind we've been having!!

The car has generally been behaving a bit weird lately, with the engine running at 600-800rpm for no apparent reason, even while rolling down a hill or being pushed by MG2 (So it's not driving the car but also not putting energy into the Battery, and not providing heat as the HVAC was off!) - May just be the recent cold snap... or... does the Mk4 have a GPF?? Maybe it's regen'ing that??

[TonyHSD]

The engine is providing heat to itself to warm up, all normal here. 😉👌

[Cyker]

I considered that but it's a bit weird as it does it whether the temp gauge is at 1 bar or 4! (out of 8 )

[TonyHSD]

1 hour ago, Cyker said:

I considered that but it's a bit weird as it does it whether the temp gauge is at 1 bar or 4! (out of 8 )

Maybe because when hot in the summer 3 bars (30-40c°) could be just fine for the engine and oil but in cold winter the engine might require more heat., or could be something else then, like discharging or charging the Battery. Lately been freezing cold outside and I keep my Auris in ready mode and every time I turn the ignition ON and the ice starts it sounds completely different from the previous time, I can feel the resistance from MG1 while charging the Battery and how the engine sounds loud and rpm remain high, then engine is running very quiet and very smooth like no resistance from MG1 at all, another time it’s just loud, like ticking sound, I also can notice when it changes rpm while going through different warm up stages etc, all can make you freaking out if you are new to the hybrids 🤣, I was like that back in 2012 when I had my first Prius but it was a company car and I wasn’t  worried at all as if something would have gone wrong I just would’ve had a replacement. Then I started to learn about these cars and the magic they have and now not been bothered by any strange or different noises. Again if something goes wrong the car will not hesitate to display message on the dashboard accompanied by many warning light ⚠️💡✅

[Cyker]

It's not so much that I'm freaking out but it's interesting seeing/noticing these new behaviours in the car. Usually I'm quite good at noticing potential issues in normal cars because they starts to feel or sound different to normal, but as you say the HSDs have a myriad of weird noises they make it makes learning what they all are and what they mean a bit tricky!  

Mostly I just let it get on and do its own thing - As long as it goes when I tell it to go and stops when I tell it to stop I leave the rest for it to figure out  

[AlJ]

I was going to add a new topic then I remembered this one! 
So, I was driving along a tree-lined, twisty country road, when I saw a cyclist ahead. As I began to pull out, a car approached round the next bend. 
I braked and pulled back in until it was safe to pass the cyclist, giving him the due distance from the car. 
Now, the thing is, about a mile further down the road, my Yaris started making a 'fluttering' noise from under the left hand side of the bonnet. I assume this was the brake booster vacuum pump, deciding to update the pressure. The sound reminded me of those pieces of plastic we put on our bicycle spokes when we were kids a long, long time ago! 
It stopped as quickly as it started, after a minute.  
A little later, a beep sounded and a message in a red rectangle appeared on the dashboard screen but immediately disappeared before I could read it. 
I drove on for about another 25 miles and nothing. No problems or odd sounds at all. 

[TonyHSD]

1 hour ago, AlJ said:

I was going to add a new topic then I remembered this one! 
So, I was driving along a tree-lined, twisty country road, when I saw a cyclist ahead. As I began to pull out, a car approached round the next bend. 
I braked and pulled back in until it was safe to pass the cyclist, giving him the due distance from the car. 
Now, the thing is, about a mile further down the road, my Yaris started making a 'fluttering' noise from under the left hand side of the bonnet. I assume this was the brake booster vacuum pump, deciding to update the pressure. The sound reminded me of those pieces of plastic we put on our bicycle spokes when we were kids a long, long time ago! 
It stopped as quickly as it started, after a minute.  
A little later, a beep sounded and a message in a red rectangle appeared on the dashboard screen but immediately disappeared before I could read it. 
I drove on for about another 25 miles and nothing. No problems or odd sounds at all. 

Something was not right then. You may have stored dtc in the ecu and if you have some sort of diy code reader it might be handy to run a quick diagnostic. Usually sounds like those from the bikes from older times are not typical for the hybrids. 

[AlJ]

1 hour ago, TonyHSD said:

Something was not right then. You may have stored dtc in the ecu and if you have some sort of diy code reader it might be handy to run a quick diagnostic. Usually sounds like those from the bikes from older times are not typical for the hybrids. 

I don't have the facility to do that but I'll pop in to the dealership next week and they can take a look at it. 

[RickyC]

On 4/2/2022 at 1:58 PM, Cyker said:

The car has generally been behaving a bit weird lately, with the engine running at 600-800rpm for no apparent reason, even while rolling down a hill or being pushed by MG2 (So it's not driving the car but also not putting energy into the battery, and not providing heat as the HVAC was off!) - May just be the recent cold snap... or... does the Mk4 have a GPF?? Maybe it's regen'ing that??

Yes,  MK4 has a GPF.  When it start regenerating the GPF,  ICE stays on longer and usually kicks in as soon as you start moving, runs at higher speed ans often charges Battery to 8 tabs keeping EV mode disabled.

Usually you see a drop on "Miles in EV mode" an MPG values in the app. 

[flash22]

It doesn't regen as such, it's more of an unmonitored cat there is no fuel injected to burn off the soot as petrols run 2-3 hotter than diesel there is just a simple pressure differential sensor

pump sounds - Water pump, Brake booster, A/C and the inverter coolant pump all are electric

https://toyota-club.net/files/faq/19-09-10_faq_gpf_eng.htm

[RickyC]

I agree that GPF doesn't need fuel injections to warmup but ICE must run cointinously at high regimen to keep filter hot.  Moreover the exaust gas is very poor of Oxygen so it's difficult to burn particulate even if the filter is hot.  

So probably the ECU switche to a B like configuration that causes a growth of fuel consumption and reduces EV support.  Some people in Italy has alredy complained with Toyota.  Some customer has supported Toyota offering to install a data capture device but after having got the data there was no more feedback.  Moreover this situation happens when air humidity is higher ( eg. rain and fog days ) 

In a thread on this forum I found a post from a French guy that described a similar situation.  I expect that it should happen also in UK considering the cooler and more rainy climate, even if I never read a post with similar complain coming from UK users. 

[TonyHSD]

What here people describe as some strange behaviour it’s actually absolutely normal for Toyota hybrids. All these noises, engine rpm’s are simply part of the hybrid experience. This particulate filter never need cleaning procedure, or perhaps happens when you take the car on motorway for 15+ minutes continues drive at speeds over 50mph. If any problems occur along the the exhaust system there will be faults detected and warning, if not at least driver will notice lost of power, and noise of gases restricted flow.