The hybrid that can't...

Thank you for the updates. I'm sure it is very frustrating for you. Following this thread has not been good for my mental health as I'm becoming worried about my brand new vehicle built in the same plant. All I can hear is that noise when I drive now.
All I would say is to take it to Toyota to look at. Maybe that will alleviate some of the mental stress. I'm not happy about it but...I get that production errors happen in the first year. The worst part is the customer service timeline to get things finalized. The dealership has been amazing though.
 
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It could also be the turbo blow off vent opening to release the compressed air. Based on the videos I have seen, the noise is primarily coming if you rev the cold engine, under these conditions, ECU would probably not allow boosting the engine and vent the compressed gas. Blow of valves definitely sound like exhaust leaks since both entail sudden release of compressed air.
Thank you, this makes so much sense and explains why it only sounds like this at cold start. I’m much more comfortable now.
 
Thank you, this makes so much sense and explains why it only sounds like this at cold start. I’m much more comfortable now.
are you? Because that same sound was tracked down to my engine cylinder 1 issue. engine torn down in pics on post 1. I'd say taking it to your dealer to have them diagnose it would be a better option.
 
It's easy to conflate a waste gate and blow off valve but they are two different things

A blow off valve is on the boost side and is to prevent boost creep or divert boost once the throttle is closed. The waste gate is on the exhaust side and bypasses exhaust gasses, so the turbo does not spool up or create too much boost. In a lot of cases the waste gate is built into the hot side of the turbo.
That is why I think the blowoff valve is more likely to cause an exhaust leak like sound, in comparison to wastegate valve. The noise from the waste gate should be more insulated since it diverts flow to/from the exhaust.
 
Out of curiosity I went out and did a cold start and heard some sounds. I definitely heard what could sound like an exhaust leak. I decided to drive it around a bit and the sound did go away after a mile or so.

This isn't my first turbo vehicle, on my other vehicles the wastegate remains open on a cold start for 1 to 2 minutes. This is true for both gas and diesel versions I have owned. It could just be a rattle from the waste gate being open.

A search on youtube will show this rattle is common across brands, not all will or are doing it but it's a potential reason. I'll wait for it to cool down and try it again while seeing if I can disable or hold the wastegate so it does not rattle.

Potential cause: wastegate rattle on cold start or under load?


Just want to make it clear this is only a theory and can and probably will be disproved
 
Any theories as to why cylinder #1 ?? Guess will know more after Toyota engineer has a look?
"the engineer removed fuel from each cylinder to locate which cylinder the noise was coming from. When removing fuel from cylinder 1 the noise went away. This lead to a total tear down of the engine (in pictures). The engineer is thinking bad universal bearing in the block. There were metal shavings in the oil as well. They are waiting for Toyota corporate to send someone out to verify the findings." --from post 1 that I updated.
 
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"the engineer removed fuel from each cylinder to locate which cylinder the noise was coming from. When removing fuel from cylinder 1 the noise went away. This lead to a total tear down of the engine (in pictures). The engineer is thinking bad universal bearing in the block. There were metal shavings in the oil as well. They are waiting for Toyota corporate to send someone out to verify the findings." --from post 1 that I updated.
I really hope this ends up well for you. I hope it’s not as bad in the end as it sounds currently- for yours & everyone else’s sake and sanity.
 
If the new ones at the dealer have the same sound then it’s most likely normal. A universal bearing what is that. The only one I can think of is the rod bearing. A bad Rod bearing isn’t likely to get silent. Someone needs to try to listen to the sound on a Tacoma.
 
If the new ones at the dealer have the same sound then it’s most likely normal. A universal bearing what is that. The only one I can think of is the rod bearing. A bad Rod bearing isn’t likely to get silent. Someone needs to try to listen to the sound on a Tacoma.
I was told that when the engine heats up that metal expands cleans up the slop essentially. I'm no engine mechanic but just relaying here. And yes. I'm pretty sure it's the rod bearing.
 
Was reading the manual, the section about fuel and found this:

View attachment 5960

Not discrediting the OP problems, but maybe for anyone else that may hear something.
weird that it says "uphill". I wonder if that's a gravity fuel delivery thing. though you'd think the spray would be pressurized enough to account for that.
 
weird that it says "uphill". I wonder if that's a gravity fuel delivery thing. though you'd think the spray would be pressurized enough to account for that.
I think they just listed most common conditions for the engine RPM to be high (going up hill and accelerating).
 
I was told that when the engine heats up that metal expands cleans up the slop essentially. I'm no engine mechanic but just relaying here. And yes. I'm pretty sure it's the rod bearing.
Should everything expand proportionally though? I know metal expansions can cover up manifold leaks, but that is because manifold and the engine block are at different temperatures. Cylinder wall and piston should be at the same temperature.
 
If the new ones at the dealer have the same sound then it’s most likely normal. A universal bearing what is that. The only one I can think of is the rod bearing. A bad Rod bearing isn’t likely to get silent. Someone needs to try to listen to the sound on a Tacoma.
That's actually a great idea wonder if anyone with a Tacoma iforcemax could confirm. Follow up to that would be... are the engines made in same plant.
 
That's actually a great idea wonder if anyone with a Tacoma iforcemax could confirm. Follow up to that would be... are the engines made in same plant.
The Tacoma is made in the Baja plant. I believe the majority of the engines for the Tacoma are built in Alabama.
 
The Tacoma is made in the Baja plant. I believe the majority of the engines for the Tacoma are built in Alabama.
Thanks. So, then another possible angle to explore is does a Tahara plant produced LC make the same sound as the Hino / Hamura ones.
 
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