Piston Engines (W/Single Or Dual EGR Valves)
- Check vacuum lines for correct routing. Disconnect vacuum hose at EGR valve, and plug hose end. Connect vacuum pump to valve. Start engine. Apply 6-10 in. Hg to EGR valve and hold.
- Engine speed should drop at least 100 RPM or engine should stall. Vacuum should not drop greater than one in. Hg in 30 seconds. Reconnect EGR vacuum hose.
Modulator Valve
Disconnect all vacuum and exhaust pipe hoses. Cap fitting going to each EGR control solenoid. Blow into bottom fitting from exhaust pipe end. Apply 7 in. Hg to fitting No. 3 (from ported vacuum source). Vacuum should hold until pressure at bottom fitting is released.
Vacuum Amplifier
- Check for adequate manifold vacuum. Warm engine and operate at curb idle. Connect vacuum gauge to vacuum amplifier port leading to EGR 3-way solenoid. Vacuum should not be greater than 1.6-2.4 in. Hg at idle.
- Disconnect venturi hose at carburetor. Increase engine speed to 3500 RPM. Vacuum should not change. Maintain high engine speed and reconnect carburetor venturi hose.
- Vacuum gauge should read 3.2-3.8 in. Hg. Return engine to idle. Vacuum gauge should return to initial reading. If vacuum gauge does not return to initial reading, replace vacuum amplifier.
Rotary Engine
Check vacuum hose routing. Disconnect EGR valve hose. Connect vacuum pump to EGR valve. Idle engine and apply 15 in. Hg. EGR valve stem/diaphragm should move and engine speed should drop at least 100 RPM or engine should stall.
EGR Solenoid Valve
- Disconnect EGR solenoid valve harness connector. Remove vacuum hose at EGR valve. Connect vacuum gauge to EGR vacuum hose. Start and warm engine to normal operating temperature.
- Increase engine speed to 1100-3300 RPM. Vacuum gauge should not read any vacuum. Allow engine to idle. Apply 12 volts across EGR solenoid valve terminals. Increase engine speed again. Observe vacuum gauge. Vacuum should be present.
MX-3 DOHC, MX-6 2.5L, 626 2.5L & 929
- Connect Engine Signal Monitor (49-9200-162) and Test Harness (49 G018 903) to ECU. Start engine. Increase engine speed, and check voltage at ECU terminals 3O and 3P while engine is cold. Voltage should be 12 volts.
- Warm engine to operating temperature, and operate it at idle. Increase engine speed, and ensure signal monitor Green and Red lights flash at ECU terminals 3O and 3P.
- Disconnect EGR solenoid valve (vacuum side) eletrical connector. Apply 12 volts and a ground to solenoid valve. Ensure engines runs rough or stalls at idle. Test EGR components as nessesary.
MX-6 2.0L & 626 2.0L
Check all connectors and hose routings. Check for cracks, leakage and restrictions, and repair as necessary.Start engine, and ensure diaphram of EGR control valve does not move while engine is cold. Warm engine to operating temperature and operate at idle. Increase engine speed to about 2000 RPM, and ensure diaphram of EGR control valve moves. If no movement is detected, test EGR components as necessary.
RX7
Check all connectors and hose routings. Check for cracks, leakage and restrictions, and repair as necessary.Start engine, and ensure diaphram of EGR control valve does not move while engine is cold. Warm engine to operating temperature and allow it to idle. Ground Blue/Yellow wire at EGR solenoid. Ensure EGR control valve moves and engine idles rough or stalls. If no movement occurs or engine idles smooth, test EGR components as necessary.
System Check
Check all connectors and hose routing. Check for cracks, leakage and restrictions, and repair as necessary. Start engine and operate throttle. EGR control valve diaphragm should not move when engine is cold. Warm engine to operating temperature. Increase engine speed to about 2000 RPM, EGR control valve diaphragm should move. If no movement is detected, check EGR valve, solenoids and EGR position sensor.
EGR Valve
Warm engine to normal operating temperature and operate at idle. Disconnect and plug vacuum hose at EGR control valve. Connect vacuum pump to EGR control valve, and apply 1.5-3.5 in. Hg vacuum. Engine should run rough or stall. If engine does not operate as specified, clean or replace EGR control valve.