Ticking From Cats

[SAMOHT023]

I have a 93 SC400 with 180,000 miles on it. I gutted the catalyc converters to increase my exhaust flow but now I get a loud ticking ticking sound from both cats. I opened them back up to make sure no material was flying around in there and they are completely empty. The car runs great besides the continuous ticking. Could the tick be an echo from those loud ticking injectors. I never heard the sound before I gutted the cats. There is no ticking from the bottom end of the motor and the only ticking I hear is from the injectors when the hood is up. Any advice? :whistles:

[JDOwen2]

Might be an exhaust leak.

[SAMOHT023]

Might be an exhaust leak.

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I thought that also. I checked carefully and replaced the gasket between the cat exit and rear pipes. Still the same thing. Just a constant tick from both cats.

[SC4Million]

Does it still tick after the car has been turned off?

[SAMOHT023]

Does it still tick after the car has been turned off?

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No tick when the vehicle is off.

[velocita]

Are you sure it doesn't do it when the car is shut off after running it?

[JIBBBY]

Are you sure it doesn't do it when the car is shut off after running it?

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THE FIRST HOLLOW SECTION OF EXHAUST EXPOSER COULD HAVE TICKING NOISE AT THAT WOULD COME FROM THE EXHAUST VALVES RIGHT THROUGH THE HEADERS DOWN TO THE HOLLOW CATS. FIRST OF ALL I AM CURRENTLY UPGRADING MY 1992 SC400 ENGINE AND EXHAUST, DID MAJOR RESEARCH AND WHEN DEALING WITH THE CATS YOU SHOULD LEAVE THOSE ALONE AS HIGH PERFORMANCE CATS MAKE YOU LOSE LOW END POWER WHILE YOU GAIN TOP END, THESE CARS ARE ALREADY SLOW OFF THE LINE DON'T MAKE IT ANY SLOWER. GO ON EBAY AND GET SOME CHEAP UNIVERSAL HIGH FLOW MUFFLERS WITH NICE CROM TIPS, SHOULD RUN YOU $50 FOR A PAIR, THAT WILL GIVE YOU MOST COST EFFECTIVE EXHAUST MOD YOUR LOOKING FOR, CATS SHOULD NOT BE CONSIDERED THE SC400 REQUIRES BACK PRESSURE FROM THE CATS.