Exhaust Gas Recirculation: Testing and Inspection

Chart C-7 EGR Check:

Wiring Diagram for Chart C-7 EGR Check:

CHART C-7


EXHAUST GAS RECIRCULATION


Circuit Description:


The digital (EGR) valve is designed to accurately supply EGR to an engine independent of intake manifold vacuum. The valve controls EGR flow from the exhaust to the intake manifold through three orifices which increment in size to produce seven combinations. When a solenoid is energized, the armature with attached shaft and swivel pintle is lifted opening the orifice. The flow accuracy is dependent on metering orifice size only, which results in improved control.





Test Description:

If a code is set, inspect EGR for damage. Disconnect the 4 wire connector at EGR. Install a fused jumper from the battery to terminal "D" of the EGR.





Start and idle engine and with a jumper, ground terminals "A," "B" and "C" one at a time. You should be able to discern a change in engine rpm as the terminal is grounded.

Terminal "A" should result in a small change and "C" in a large change in rpm. The engine may stall when "C" is grounded.