MK4 Yaris Hybrid occasionally making loud pump noises?

[mjjferreira]

On 4/2/2022 at 12:58 PM, Cyker said:

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??

I just received my yaris hybrid and it seems to do the same noise. (Seems like a hammer hitting the engine)

The noise happens in first start, when engine is still cold and usually when the Battery is low (3 bars).

After some minutes of drive is doesn't happen anymore.

It's loud and very anoying!

My Corolla TS MY21.5 2.0 never does that!

Are you guys sure it's a normal behaviour?

 

[Cyker]

I can't say for sure without hearing, but I will say mine has that dieselly dakka when the car is stationary and charging the Battery, but it is also a bit dakkary when it's going through its first-start morning warmup procedure, where the engine is running but not driving the wheels.

It is quite obnoxious tho', and really stands out because the car is normally exceptionally smooth!

The worst thing is when you're stuck in traffic, not moving, in virtual silence... then it suddenly starts to do it; Ugh! It's really made me alter my routes to avoid jams, even if the route is twice as long, because it's so obnoxious.

The 4-cylinder engines are far less rattly, so I'm currently operating on the theory it's all due to the Yaris having an unbalanced 3-cylinder engine.

Assuming you're talking about the same thing, I'm assuming it's normal as everyone else with the same car seems to have the same experience.

I've had mine a while now and it's had a good mix of slow traffic and fast twisties and it still does it when stationary, but hasn't shown any signs of problems so far!

[TonyHSD]

1 hour ago, mjjferreira said:

I just received my yaris hybrid and it seems to do the same noise. (Seems like a hammer hitting the engine)

The noise happens in first start, when engine is still cold and usually when the battery is low (3 bars).

After some minutes of drive is doesn't happen anymore.

It's loud and very anoying!

My Corolla TS MY21.5 2.0 never does that!

Are you guys sure it's a normal behaviour?

 

Does it do it every cold start when Battery is low or not every? Can you record the noise that is worrying you ?
 

Sometimes noises on cold start like mental clunks and bangs can happen because of the engine electric motor set up, and also where and how the car was stopped ( parked), when the engine starts the whole car is trying to move if you had noticed and if the transmission lock pole is In odd position there is possibility of slight click ( clunk) to occur.
When Battery is low the mg1 will add extra resistance to the engine and the clutch dampener can also clunk once. If only does it once then it’s likely any of the two possible scenarios, if it’s rattling continuously then it’s not right and it’s something else.  

[mjjferreira]

10 hours ago, Cyker said:

I can't say for sure without hearing, but I will say mine has that dieselly dakka when the car is stationary and charging the battery, but it is also a bit dakkary when it's going through its first-start morning warmup procedure, where the engine is running but not driving the wheels.

It is quite obnoxious tho', and really stands out because the car is normally exceptionally smooth!

The worst thing is when you're stuck in traffic, not moving, in virtual silence... then it suddenly starts to do it; Ugh! It's really made me alter my routes to avoid jams, even if the route is twice as long, because it's so obnoxious.

The 4-cylinder engines are far less rattly, so I'm currently operating on the theory it's all due to the Yaris having an unbalanced 3-cylinder engine.

Assuming you're talking about the same thing, I'm assuming it's normal as everyone else with the same car seems to have the same experience.

I've had mine a while now and it's had a good mix of slow traffic and fast twisties and it still does it when stationary, but hasn't shown any signs of problems so far!

I noticed another thing this morning, at first run. (engine still cold)

While moving and ICE is on, when i take the foot out of the accelerator (hybrid system starts re-charging) i hear a sound, like a small machine gun, from the engine. As soon as i accelerate again, the sound is gone.

Does this happen to you guys too?
 

This engine (hybrid system), the sounds it makes, it's completly different from the hybrid system on my corolla TS 2.0 MY21.5

[mjjferreira]

10 hours ago, TonyHSD said:

Does it do it every cold start when battery is low or not every? Can you record the noise that is worrying you ?
 

Sometimes noises on cold start like mental clunks and bangs can happen because of the engine electric motor set up, and also where and how the car was stopped ( parked), when the engine starts the whole car is trying to move if you had noticed and if the transmission lock pole is In odd position there is possibility of slight click ( clunk) to occur.
When battery is low the mg1 will add extra resistance to the engine and the clutch dampener can also clunk once. If only does it once then it’s likely any of the two possible scenarios, if it’s rattling continuously then it’s not right and it’s something else.  

Today when i started the car, it had 6 bars...and 5 seconds after i pressed the start button, the engine turned on.

When i was exiting the garage it started making those weird loud knocking sounds. Its not constant, during the trip to work it almost never does it. (Probably engine is warmer)

[Trewithy]

I've had two 3 cylinder cars in the past and based on my experience I would not have another one.  They both vibrated and sounded like a diesel at certain revs.  A shame really as the size of the Yaris Cross would suit me.  

[Max_Headroom]

Why did they move from the 1.5 four cylinder of the MK3 to a 3 cylinder there doesn't seem to be much that regularly goes wrong with it (if anything) why didnt they stick with what they know.

[TonyHSD]

Probably a production cost, the engine is very much a 2.0 version minus one cylinder. I had a good lock around today of Yaris cross and I did liked it a lot. The size of the car is small, smaller than Corolla hatch in fact , however inside has somehow more room, higher roof line makes it slightly more practical. Front seats very comfy, rear ones seat base it’s fine but the back rest it’s not as good as on Corolla, Yaris has an odd angled back rest , a bit too upward. Boot space is perfectly fine. Tough choice between Corolla hatch and Yaris cross. Yeah, the 3 cylinder engine is a bit err, but they seems very popular, perhaps people get use to them. 

[Max_Headroom]

34 minutes ago, TonyHSD said:

Yaris has an odd angled back rest , a bit too upward.

Thats good news for me i always sit close to bolt upright.

 

Quote

Yeah, the 3 cylinder engine is a bit err, but they seems very popular, perhaps people get use to them. 

How long have Toyota been using this engine are thy reliable?

 

[TonyHSD]

26 minutes ago, Max_Headroom said:

Thats good news for me i always sit close to bolt upright.

 

How long have Toyota been using this engine are thy reliable?

 

2 years. I think it’s a bit early to say how reliable they are indeed but overall they seems fine. 👍

[Cyker]

2 hours ago, Max_Headroom said:

Why did they move from the 1.5 four cylinder of the MK3 to a 3 cylinder there doesn't seem to be much that regularly goes wrong with it (if anything) why didnt they stick with what they know.

I did wonder that, but probably an efficiency thing, as 3 cylinder engines have more torque and less parasitic loss than a similar 4 cylinder engine (Each cylinder is 0.5L!! If it was a 4 cylinder they'd only be 0.38L each.)

Also takes up less space and would be a fair bit lighter, less reciprocating mass etc.

There are a lot of advantages but refinement isn't one of them!

To be fair it could be worse - They could have copied Fiat and gone to 2 cylinders!!    

 

 

12 hours ago, mjjferreira said:

 

I noticed another thing this morning, at first run. (engine still cold)

While moving and ICE is on, when i take the foot out of the accelerator (hybrid system starts re-charging) i hear a sound, like a small machine gun, from the engine. As soon as i accelerate again, the sound is gone.

Does this happen to you guys too?
 

This engine (hybrid system), the sounds it makes, it's completly different from the hybrid system on my corolla TS 2.0 MY21.5

Yea I get that in the morning too - When the engine is going through its warmup phase it's basically idling and charging the Battery, but the electric motors are driving the car. If you ask for more power tho' the car will rev the engine up a bit and use it to drive the wheels, and I guess the higher revs make it smoother??

You keep describing it like a machine gun or hammering - Is it really that harsh or is it really more like diesel knock/clatter like from e.g. a bus or lorry?

I ask, because if it is much harsher than diesel knock and actually sounds like rapid impacts it might be an actual problem - e.g. There have been cases in some early batches where a plate connecting the engine to the hybrid system wasn't bolted on properly and became detached, causing a hybrid system error and car to shut down, and I would imagine the precursor to that happening might be some hammering noises if it became loose!

You could also try better quality fuel as some members find they run a bit smoother than the regular stuff.

[mjjferreira]

1 hour ago, Cyker said:

You keep describing it like a machine gun or hammering - Is it really that harsh or is it really more like diesel knock/clatter like from e.g. a bus or lorry?

More like a diesel knock

[Cyker]

Ahh, in that case I reckon you're okay as that's just the same noise all us Mk4 owners are getting.

Just be glad it isn't a mid-2000s Bluemotion Polo (Diesel AND 3 cylinders... horrible engine!!  )

[bathtub tom]

4 hours ago, Max_Headroom said:

Why did they move from the 1.5 four cylinder of the MK3 to a 3 cylinder there doesn't seem to be much that regularly goes wrong with it (if anything) why didnt they stick with what they know.

Fewer moving parts=better efficiency.