06 Camry cold start noise?
 

2006 Camry 2.4L Auto 80,000 mi
In cold weather, after car sits a few days, engine is noisy, then noise goes away after a few minutes.
Car has been great, only changed Alternator and belt, so far.

Use a section of hose a stethoscope to attempt to narrow down the area of the noise.

Check the passengers side of engine from top to bottom. Areas around the serpentine belt tensioner, water pump and intake cam pulley.

I was thinking it my be cam/valves and lack of lubrication after sitting a few days???

Could be.

The engine has a variable valve train timing mechanism on the intake camshaft pulley. This mechanism can rattle at cold start from lack of oil pressure. Location is on the engine facing the passengers front tire and back toward the firewall.

Or the timing chain can rattle. This goes around inside the circumference of the metal cover on the passengers side.

Or serpentine belt tensioner. Location passengers side of engine towards firewall.

Using the section of hose, one can narrow down the area of the noise. Some items are easier to fix then others.

All are common problems.

Thanks for the guidance, I will do what you say, but I'm under the weather now.
This car is often not driven for days at a time, so it rattles on startup.
If it's driven yesterday, today's startup will not be problematic.
Question:
Do all of the above issues you mentioned require immediate attention?

No.

Rattle on cold start of this engine is a common complaint.

Monitor noise in case it starts to get worse.

This engine model can have an issue with using oil due to a piston design problem. Check oil level every 500 miles.

Suggest using synthetic of the recommended weight specified by the owners manual. This will help prevent future oil burning due to piston ring oil drain holes plugging up with varnish.

Thanks greatly! The fact that It's not urgent is a relief.
The synthetic oil, I will do that.

Thank You