5vz engine nose

[Adam F]

97 4Runner Limited 5vzfe. 267k. Runs like a top. Always well maintained. T-belt done 10k ago.

Normally I don't rev it high, but for the past month, when i do, above 4500 or so, it makes a rattling noise. Sounds like something in the valvetrain. Has me worried. I tow a big boat and will often have to rev it high to climb hills.

Anyone ever experience this? Where do I start with a diagnosis? Pull valve covers and check valve clearance?

 

[Stiles97]

Exhaust rattle? Maybe you have a heat shield that is loose. That was the first thing to come to my mind.
Matt

 

[Adam F]

I hope, but this sounded pretty loud and coming from under the hood.

 

[Raintrees]

Could be a number of things try getting a video of it.