Honda Civic. Manual — part 353

Fig. 2: Identifying Catalytic Converter Remove/Install Components (With
Torque Specifications)

4. Remove the TWC (B).
5. Remove the converter cover (C).
6. Install the parts in the reverse order of removal with a new gaskets(D).

2008 Honda Civic GX

2006-08 ENGINE PERFORMANCE Catalytic Converter System - Civic GX

2006-08 ENGINE PERFORMANCE

Catalytic Converter System (K20Z3) - Civic (All Except Si)

COMPONENT LOCATION INDEX

2008 Honda Civic GX

2006-08 ENGINE PERFORMANCE Catalytic Converter System (K20Z3) - Civic (All Except Si)

2008 Honda Civic GX

2006-08 ENGINE PERFORMANCE Catalytic Converter System (K20Z3) - Civic (All Except Si)

Fig. 1: Identifying Catalytic Converter System Component Location
Courtesy of AMERICAN HONDA MOTOR CO., INC.

DTC TROUBLESHOOTING

2008 Honda Civic GX

2006-08 ENGINE PERFORMANCE Catalytic Converter System (K20Z3) - Civic (All Except Si)

DTC P0420: CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD

1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (in neutral)

until the radiator fan comes on, then let it idle.

4. Test-drive under these conditions:

Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)

Transmission in 5th gear

Vehicle speed between 45-75 mph (72-120 km/h) for 5 minutes or more
with cruise control set

'06 model: Maintain the vehicle speed at 55 mph (88 km/h) for 5 minutes
or more with cruise control set

'07 model: Maintain the vehicle speed at 55 mph (88 km/h) for 30 seconds
or more

5. Monitor the OBD STATUS for DTC P0420 in the DTCs MENU with the

HDS.

Does the screen indicate EXECUTING?

NOTE:

Before you troubleshoot, record all freeze data and any
on-board snapshot, and review the general
troubleshooting information (see GENERAL
TROUBLESHOOTING INFORMATION ).

If some of the DTCs listed below are stored at the same
time as DTC P0420, troubleshoot them first, then
recheck for DTC P0420.

P0137, P0138: Secondary H02S (Sensor 2) P0141:
Secondary H02S (Sensor 2) heater

Poor quality fuel may cause this DTC.

2008 Honda Civic GX

2006-08 ENGINE PERFORMANCE Catalytic Converter System (K20Z3) - Civic (All Except Si)