EX3 - Vacuum Test, Converter On, Muffler Off

^ Turn the engine off.

^ Reconnect the exhaust system at the exhaust manifold.

^ Disconnect the muffler.

^ Repeat Test EX1. Is the manifold vacuum above 508mm (20 in) of mercury?

YES -- REPLACE the muffler.

NO -- REPLACE the three way catalytic converter and INSPECT the muffler to be sure converter debris has not entered the muffler. GO to Test EG8. EG8 - Rerun Exhaust Gas Emission Test