Exhaust Gas Recirculation: Service and Repair

The EGR system must he cleaned every 25,000 miles. Remove the EGR valve, clean the valve seat, the connecting pipes and the pipe leading to the intake manifold. Reassemble and check the EGR valve operation. On 1974-75 vehicles, start the engine and press in the switch on the throttle linkage. The engine idle should falter indicating proper operation. On 1976-82 vehicles, connect the EGR control valve to a constant vacuum source and start the engine. On models with a backpressure activated type EGR valve, raise engine speed to approximately 2000 RPM. Engine idle should falter when vacuum is applied to the valve indicating proper operation. A maintenance indicator, inserted in the speedometer cable, closes an electrical contact which illuminates a warning light on the dashboard, indicating the system is due for maintenance. After completion of the EGR service, the maintenance indicator can he reset as follows:

Fig.12 - Resetting EGR System Maintenance Reminder Indicator:

1. Remove the cover (C) on the maintenance indicator, Fig. 12.

2. Turn the knob (B) A turn in the direction of the arrow towards mark 0. This will turn off the EGR warning light and restart the indicator for a new maintenance cycle.