When I start the engine I don't hear anything but after a few minutes I start hearing a tap. What could this be? I first noticed it a few months ago after getting an oil change but a few days before that I changed all my belts could it be a loose belt or the wrong oil?

I usually use 5w30 I think they put in 10w30 but I'm not sure.
Definitely not a squeal but a tap if I press the gas in neutral the taps go faster. It's an '03 with 170,000 on it

 

Might want to post a video on YouTube and link it here.

 

Could be a lifter. These cars utilize a solid valve train, so when components wear over time things tend to open up, which can create noise. Are you using synthetic oil?

 

This is what I use and I'll post a video tomorrow