2001 S60 (2.4L) check engine light on and strange sound

[LUINGOR]

Hi,
Just over the past weekend, I drove the car just after Hanna Storm past my area to fill the tank, and later that day, the check engine light came on and I might smell like something burning or smoking for a minute (but I am not sure it's from my car because I didn't smell it when I was aware of the strange smell and then slowed down a little bit). Actually, the check engine light came on two or three times before and then went out a day or two later automatically, so I guess that could be something wrong with the indicator light, but now I don't think my guess is right. Do I need to bring the car to a shop to check it and see if any sensor or part needs to be replaced? Can I drive with the light on for days? I am just afraid it will break down on the way to work or on highway. Any one knows anywhere is free to help check what the problem is?

It has another problem: I heard a tinkle from the underneath frequently, like the friction between two pieces of metal, especially when I put my foot on the accelerator pedal. When I noticed the sound, I released the accelerator pedal, and then the strange sound disappeared. It doesn't affect the car or my driving, but I just feel it's annoying and wonder if this could be a sign of big problem or not.

P.S. I got a lot helps here and really appreciate it. Thank you guys!

[sony2000]

I'm thinking that part of the internals of the catalytic converter broke off, and is floating around inside.

[MadeInJapan]

sony might be right but if the check engine light (CEL) is going on and off check your trouble codes...I'm sure that there are impending ones even if the light is off at the time.