[Rawbertd]

Hi, hoping some of you guys might be able to help me out. Been dealing with this weird rattling noise, sounds like metal hitting each other. I can hear it inside and outside of my car. The only codes I have on my matrix is P0420 with 205k miles with rebuilt engine. I’ve also been dealing with lack of acceleration, I struggle driving up steep hills. I also started having shifting issues when I did a simple drain and fill but after adding trans tune my matrix is shifting normal but noticed lack of acceleration. Any advice? Thanks!

Here’s a YouTube video of the rattle

 

[elitemafia]

That is not a noise I'm familiar with... but the p0420 is usually bad o2 sensors which are fairly easy to replace. That said unless the cat is bad, o2 sensors usually don't cause major issues with the engine performance like that. Cat probably wouldn't make that noise though. It sounds like something in the motor is rattling around, like a failed bearing or something.

 

[Rawbertd]

Noise doesn’t increase with higher rpms.. I was thinking maybe a broken timing chain tensioner?

 

[75aces]

Sounds like noisy cam shafts or the flat plate under the valve cover has been bent downward and is hitting the exhaust cam shaft.

For the decreased acceleration, I would suggest you try using Chevron fuel system cleaner at your next fill up.

Do you know if the intake manifold gasket has ever been serviced? Look to see if it's orange. If it isn't, then it still has the older version.

You can also inspect the butterfly plate in the throttle body to see if there's carbon buildup preventing the plate from operating normal.

 

[Supersonic]

Might have to remove the valve cover, but the oil fill has a metal shield inside that can get bent and hit on the cam if someone has tried to stick a funnel or oil fill device into it too aggressively.

Also try removing and cleaning the VVTi oil control valve and screen. They are feed by the oil pump, I'd hope it's not that.

Start with the simple stuff, but next, the cam phaser might be making a similar noise, go check some of the 2009 Corolla examples, I think there might be a few examples being it is a big problem with them on that year.