Exhaust System: Service and Repair

Removal and Installation
Refer to the figures for removal and installation.

Exhaust System (QG18DE):

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 mm (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 clearer fool, 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.