Exhaust System: Service Precautions

CAUTION:
^ Always replace exhaust gaskets with new ones when reassembling.





^ For the QR25DE engine, install the front combination seal bearing as shown. Position the conical spring so that the wide end is against the flange as shown.
^ With engine running, check all tube connections for exhaust gas leaks, and entire system for unusual noises.
^ Check to ensure that mounting brackets and mounting insulators are installed properly and free from undue stress. Improper installation could result in excessive noise or vibration.
^ Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7 inch) onto a hard surface such as a concrete floor; replace it with a new one.
^ Before installing a new oxygen sensor, clean exhaust system threads using oxygen sensor thread cleaner tool, J-43897-18 or J-43897-12, and apply anti-seize lubricant.
^ Do not over-tighten the oxygen sensor. Doing so may cause damage to the oxygen sensor, resulting in the MIL coming on.
^ If the Calif. CA models TWC (manifold three way catalyst) or ADS-TWC (adsorber pre-catalyst) replacement is necessary, always replace the TWC together with the ADS-TWC. Never replace these catalysts individually. The TWC and the ADS-TWC are only available together as a kit.