Why is the engine of my 2010 Toyota Corolla LE making this sound?

[flow321]

For the last year my car has been making this noise every time I turn on the ignition, especially in the mornings when it's cold. When the weather is nicer it's less noticeable. For those of you who are car maintenance experts, what do you think it could be? I've taken it to two mechanics so far and each one of them tells me they've solved the problem and then after a day the noise is back. I've never done maintenance work on my car before, but paying mechanics hasn't worked so I'm thinking maybe I should give it a try. The link below is a video so you can hear the noise. All help is welcome, thanks.

https://youtu.be/YehMOI5h7go

[lutorm]

Do you mean when you start it? I can't quite hear what happens before you start it in the video, but the rattle right when it starts that then goes away sounds to me like hydraulic lifters with a lot of play that then pumps up as oil pressure comes up. 

[sonofsven]

Did any of the mechanics replace the starter?
Or look at the flywheel engagement with the starter?
This is where Tom and Ray start arguing on Car Talk...
RIP Tom

[DeniseNJ]

https://www.youtube.com/watch?v=gwJ5BBHb9W4
This sounds just like your rattle. But it looks like more than a beginner should be doing.  Call the guys you took it too and ask what they thought it was and what they actually did to the car.
Someone else said it could be timing chain.  Do you have a chain or belt?

Google "rattle on cold start" and your engine type, so you can check if they stuff people are saying is common is stuff your mechanics checked.

[flow321]

Do you mean when you start it? I can't quite hear what happens before you start it in the video, but the rattle right when it starts that then goes away sounds to me like hydraulic lifters with a lot of play that then pumps up as oil pressure comes up.

Good morning, at the beginning of the video there isn't any sound because I didn't turn on the car yet. Thank you for your answer. What could have caused this to happen?

[flow321]

Did any of the mechanics replace the starter?
Or look at the flywheel engagement with the starter?
This is where Tom and Ray start arguing on Car Talk...
RIP Tom

I'll be honest I didn't ask because I didn't know I should. Now that you've provided me that information, I'll ask the next mechanic or see if any of my friends are handy with cars.

[flow321]

https://www.youtube.com/watch?v=gwJ5BBHb9W4
This sounds just like your rattle. But it looks like more than a beginner should be doing.  Call the guys you took it too and ask what they thought it was and what they actually did to the car.
Someone else said it could be timing chain.  Do you have a chain or belt?

Google "rattle on cold start" and your engine type, so you can check if they stuff people are saying is common is stuff your mechanics checked.

You're right, it does sound like the rattle in my car. Yeah I'll call tomorrow. Honestly I don't know if I have a chain or belt.

Ok thanks for your advice, I'll Google it and see what I find.

[lutorm]

Ah, valve timing adjuster? Yeah, I'd believe that. I had a similar sound on my 1.8T Passat, going off/on throttle it would make a rattle. That's when the camshaft timing adjustment mechanism actuates, and the oil screen was plugged so the oil pressure took a second to build up enough to push it into the actuated position, and until then it would rattle. Luckily it was still under warranty.

[jlivingstone]

My 2009 Corolla makes the same sound, and it was diagnosed as a problem with the VVT.  They told me not to worry about it unless the noise bothered me $900 worth.  Pretty much spot on with that video that was posted.

[Model96]

Yep, VVTI actuator needs replacing. Sometimes they make a ticking noise when you are cruising along at light throttle.