Another one of those - is this sound normal posts........... :o

2023 Pro- makes a "strange" sound on cold startup..........
Sounds like a metal clank - either something from oil pressure buildup (VVTi?) or air pressure buildup (smog?).
This isn't my truck in the video, but you can hear the "clank" in this person's 4R immediately after the startup - just a split second after it fires. I was glad to hear it in this video - makes me think I'm at least not the only one.
I'm curious what it is, though, even if it is normal, but especially if it is not normal!
https://www.youtube.com/shorts/8REbfgZppwQ

 

Normal. Moving on...

 

Replayed a couple times, can't hear anything weird to me in that

 

Just over 90K miles on my 19 and it does this daily. Just keep driving it.

 

Appreciate it is normal - but does anyone know what is making that noise? It is obviously not piston slap, lifters, or any other sort of typical cold start rattle phenomenon.

 

Sounds like a new truck to me.

 

I figured it was the transmission internals taking up slack or fluid pressure relief as you started the engine. I'll take it over the Chrysler transmission rattle.

 

I’ve heard the sound you’re talking about. My 24 has it sometimes, and some cold starts/ starts it doesn’t do it at all. I believe it’s normal, I’ve heard it on other 4Runners before.., and you have to listen very carefully. Happens for about .1 seconds and that’s it


At least we don’t have timing chain rattle on startup

 

Yep - super quick and I imagine some people never "hear" it. I definitely don't notice it everytime.

 

I’ve heard the cold start clatter is the hydraulic Vvti system, which has to pressurize and get oil in them.

 

normal