2003 Camry LE 2.4, Knock in engine, 213K miles.
 

I just bought the car and now it has a knock... It doesn't sound like a lifter, but can hear it through the valve cover. Almost seems like there is a deeper quieter knock also.. These are usually bullet proof motors. I changed the oil right after I bought it (5w30 full Synthetic.). I did add a half can of seafoam high mileage motor treatment before draining it. The car runs fine. I feel like the noise isn't a problem, but... What say ya'll?

How many miles between purchase and knocking noise?

Was the knock present before the oil change?

Knock at cold engine start, engine warm, both?

When you rev up the engine does the knock get louder as the RPM's DECREASE?

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

The engine uses a timing chain system that can rattle with wear thus listen for rattles at the front of the engine. Plus a rotating balance shaft under the crank whose gears can fail.

YouTube has video's with audio for rod bearing knock, main bearing, knock, etc and some for the same model engine. Compare video's to your noise.

Thanks for the reply.

How many miles between purchase and knocking noise? Maybe 650.

Was the knock present before the oil change? No.

Knock at cold engine start, engine warm, both? Not at start up and initial high idle (cold). The faint knock sound was at initial start up. It seems like the noise is there once the motor is p to temp?

The rest of these questions I will check in the next day or two. THANK YOU

When you rev up the engine does the knock get louder as the RPM's DECREASE?

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

The engine uses a timing chain system that can rattle with wear thus listen for rattles at the front of the engine. Plus a rotating balance shaft under the crank whose gears can fail.

YouTube has video's with audio for rod bearing knock, main bearing, knock, etc and some for the same model engine. Compare video's to your noise.

Thanks for the reply.

How many miles between purchase and knocking noise? Maybe 650.

Was the knock present before the oil change? No.

Knock at cold engine start, engine warm, both? Not at start up and initial high idle (cold). The faint knock sound was at initial start up. It seems like the noise is there once the motor is up to temp?

The rest of these questions I will check in the next day or two. THANK YOU

When you rev up the engine does the knock get louder as the RPM's DECREASE?

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

The engine uses a timing chain system that can rattle with wear thus listen for rattles at the front of the engine. Plus a rotating balance shaft under the crank whose gears can fail.

YouTube has video's with audio for rod bearing knock, main bearing, knock, etc and some for the same model engine. Compare video's to your noise.

Rod knock
 

It sounds to me like you have a little too much rod bearing clearance. I think the engine had thicker oil prior to you changing to the 5w30. You hear the noise more as the engine warms up because the oil is getting thinner as it heats up. If it was a timing chain noise I don't think it would get worse as it warms up.