okay, this has been going on for a while, but i have no idea what it is. sometimes... only sometimes, i will be at a red light, and this loud chugging, ticking noise will start up. it seems to be coming from the passenger side. I'll get out of the car and check it out and you can hear it really loudly from near the passenger side wheel well. has anyone else had this problem?

is it an exhaust leak? is it a really messed up RR or valve?

 

My guess is exhaust leak. Maybe even a rusted out cat converter. My cat converter rattled and made all kinds of noise when it went bad.