I know that you can test if a catalytic conveter is brocken by hitting it w/ your hand or something, and if it rattles it means that is brocken.

well my car is a little too low to the ground and i can't get under it, plus i haven't had time to take it in to a mechanic....but my check engine light is on, and i can hear a rattling noice from my muffler...yet i tried a diagnostic test at the local autozone and no codes came up....Whats going on???

is my converter definetly brocken???

 

since u guys are not helping me out...let me put it simple

say is broken....am i better off buying a new catalytic converter or a test pipe...
wat are the difference, gains in power output, soud, etc.

bumpppppppppppppp

 

what year is your car...? if it is obd1 and the cat is bad(it shouldn't throw a cel...)

however if it is an obd2, then that might be it... replace the cat.

 

2002 Civic, anyone else....c'mon

bump

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jalow69 &raquo;</TD></TR><TR><TD CLASS="quote">2002 Civic...</TD></TR></TABLE>OK, NOW there's something to go on. I was just about ready to reply that a 1977 Civic doesn't even have a cat...

Your car is OBD-2 so if the cat is functionally bad, it should throw a CEL. But rattling just means the ceramic is breaking up. Maybe it has to get worse before it throws a CEL.

The rattling might be exhaust heatshields. You gotta get under there & check that out. You should always check & rule out the easy, silly stuff first.

If it turns out to be a bad cat, remember you've got an 80k mile warranty on that.