I have a 2009 scion tc manual transmission, recently it has started making this ticking and or rattling sound. It only happens after the engine is warmed up and sometimes it will come in and out, and its loud enough where you can hear it in the drivers seat when the radio and ac is turned off, then It either goes away or stops after about 3000 rpm I have an aftermarket exhaust on it so I can't tell, I had a family member that is an auto tech take it in and look at it and he used a listing device and found it loudest in the exhaust near the engine, what could it be?
We'll make sure there's no exhaust leaks which is easy to do just put a smoke machine in the tailpipe and if the smoke comes out by the headers you know there's a leak there but it's not leaking off and it can be exhaust valves radially but you're right near the exhaust from old age
