New Yaris Hybrid - weird and loud noise from the engine

[anchorman]

2 hours ago, Cyker said:

I don't think the OP's issue is the 'normal' diesel-esque knock the M15A has at lower revs, as the way he's described it it sounds much more severe, but it's hard to know without hearing a recording of the sound.

I'm less sensitive to that rough engine vibration sound because I'm a diesel person, but I could imagine anyone coming from e.g. the buttery-smooth 1NR-FE being a bit surprised and concerned about how unrefined the M15A is when it's at low RPM, and even I find it quite obnoxious when it's charging while stationary, to the point I'm taking alternative routes to try and avoid being stationary, even if they are longer!!)

The engine sounds best at 2k rpm and above for sure, then it develops a nice growl  

 

Mine makes a strange noise for a few minutes after cold start.  It’s like a second hollow engine noise but it goes so I’m convinced it’s the charcoal filter circuits cutting in and out.  Gilbert O’Sullivan at volume 10 cures it completely.  

[Nixy]

Hey why not use a balancer shaft? Let's not sacrifice everything for the sake of absolute efficiency. I still insist this awful noise is unacceptable! 

[Rhymes with Paris]

1 hour ago, anchorman said:

Mine makes a strange noise for a few minutes after cold start.  It’s like a second hollow engine noise but it goes so I’m convinced it’s the charcoal filter circuits cutting in and out.  Gilbert O’Sullivan at volume 10 cures it completely.  

Gilbert O'Sullivan ,😱 that is a serious mechanical problem.

Can you not try other 70s tracks, perhaps Mud's tiger 🐯 feet, or even Slade in an emergency noise situation.

[Ken Adams]

On 10/27/2022 at 5:06 PM, mjjferreira said:

It sounds like mine.

2 questions:

- Is the sound during those 30 seconds similar to a knocking sound?

- Does it happen every day?

Yes, It only happens when starting from cold. it's definitely a mechanical knocking sound like a compressor. I was given the "They all do that sir, its normal" response from the dealer, but was not given an explanation of the cause, only its part of the normal warm up sequence.

[TonyHSD]

Can someone record these loud knocking noises on cold start once from outside the car and from inside? 
While might be normal and all does these it might not be or perhaps we need an explanation while is that? 

Sometimes noises like that can occur from exhaust back box (silencer) because of condensation and water forming inside, you can have as much as 1 litre of water splashing in your silencer and on cold start the extra water from the condensation can choke the gasses that are passing through the pipe creating a gurgle noise. This particular event is very common on cars that been used mostly on short town trips, cold weather, and 3 cylinder engines. 
Does the car sounds anything similar to this? 

 

[mjjferreira]

No, not like that.

After my car returned from the leadership, the noises have gone.

However, it doesn't mean that the issue is gone.

i know for sure that the constant rumble i was hearing is fixed and it was due to the exaust line being loose.

i just don't know if it was also the root cause for the "hammer" noise i was hearing sometimes in the morning. Next weeks will be crucial...for now is all smooth!

 

[Max_Headroom]

Does it sound like this - 

 

 

 

 

[mjjferreira]

I never heard it from the outside, therefore it's hard to have 100% sure, but its similar to that.

[Max_Headroom]

Could you post a video of the sound.

[mjjferreira]

Once it happens again...i will try to record it.

[TonyHSD]

1 hour ago, mjjferreira said:

I never heard it from the outside, therefore it's hard to have 100% sure, but its similar to that.

This knocking noise comes from the clutch plate damper springs as a result of engine misfire caused likely because of a problems related to the egr.
My car does that sometimes on cold starts for few seconds, usually when the car hasn’t been used for some time. I will be cleaning egr system soon. I did at 136000 miles and since then very rare has had happened, but recently has started to do it again more often., perhaps needs cleaning again at 227000 miles. Your one it’s brand new and should not do anything like that at all., it’s not normal occurrence unless there is something else that upsets the normal engine operation. 

[Phil Dan]

Hi guys, I have the new Yaris Launch now done 2,000 miles.  

I also have this noise. 

Just had it's first service and the dealer is concerned but not sure.

I suspect crankshaft damper

 

[RobertR]

On 10/28/2022 at 7:48 PM, Nixy said:

Hey why not use a balancer shaft? Let's not sacrifice everything for the sake of absolute efficiency. I still insist this awful noise is unacceptable! 

• Balancer shaft is not used - the engine operating range at hybrids allows it.

• The unbalanced weight is built into the crankshaft pulley, which reduces the vertical component of vibrations typical of a 3-cylinder engine.

 

I don't say it's excused, just deal with it or swap the car, you don't do with that noise and vibration nothing.

[Nixy]

OK RR. THANKS. 

[TonyHSD]

Damper (clutch) can cause knocking noises however that doesn’t mean it’s broken, or broken of yet, the question is what causes the engine to vibrate (shake violently ) to disturb the damper? In older generation hybrids this is common fault of egr system, blockage. They should look into that matter and check. 👍