1.4 & 1.7L
- Disconnect vacuum line at EGR valve vacuum port and connect vacuum pump to vacuum port. With engine at normal operating temperature and at curb idle, apply vacuum to EGR valve. This should cause an immediate drop in engine speed and indicate EGR valve has been properly preventing flow of exhaust gases to intake manifold at idle speed.
- If engine speed does not drop, passage between EGR valve and intake manifold may be plugged. If engine idles rough but is not affected when vacuum is applied, fault is in EGR valve, gasket or intake manifold.
- If engine idles properly, but there is no change in engine speed when vacuum is applied to valve, exhaust gases are not reaching intake manifold. There is probably a plugged passage from EGR valve to intake manifold or, vacuum control diaphragm is broken.
- Vacuum for EGR valve is controlled by a solenoid. When solenoid is energized by ECU, it prevents vacuum signal to EGR valve. Solenoid is energized during engine warm-up, closed throttle (idle), wide open throttle and rapid acceleration.
NOTE:
DO NOT disconnect solenoid without first turning ignition switch off. If solenoids are disconnected, EGR valve will be operational at all times.