626 2.0L (Using New Generation Star (NGS) Scan Tool)
- Warm engine to normal operating temperature. Connect NGS scan tool to Data Link Connector (DLC). DLC is located under left side of instrument panel, right of steering column. Using scan tool, access DIAGNOSTIC DATA LINK menu, and select PCM. Highlight and select PID/DATA MONITOR AND RECORD.
- Turn ignition on. Select FHO2S PID for front sensor or RHO2S PID for rear sensor. See PIN VOLTAGE/PID VALUE CHARTS article. If voltage is not as specified, check wiring harness between PCM and HO2S. Also check intake manifold system, fuel system and self-diagnostic system. Repair as necessary. If no problems are found, replace HO2S.
- To test HO2S heating element, allow sensor to cool to room temperature. Disconnect HO2S connector. Using ohmmeter, measure resistance between terminals "B" and "C" for 3-terminal sensor or "C" and "D" for 4-terminal sensor. see scheme 18 Resistance should be about 6 ohms at 68°F (20° C). If resistance is not as specified, replace HO2S.
System Inspection
Purge system operation takes place when vehicle is accelerating in gear (off idle), engine is at operating temperature and oxygen sensor is functioning normally. Ensure all vapor lines are connected and in acceptable condition. (Scheme 16), (Scheme 17) or (Scheme 18).
Note. Evaporative emission system schematic for 626 is not available from manufacturer.
Scheme 16
Scheme 17
Scheme 18
Verify that engine coolant temperature is less than 68°F (20°C). Start engine and operate at idle. Remove Positive Crankcase Ventilation (PCV) valve, with hose attached, from valve cover. Block PCV valve opening and check for vacuum. If no vacuum is felt, check for collapsed or blocked PCV valve hose. Repair as necessary. If hose is okay, replace PCV valve.
VACUUM LINE INSPECTION (MILLENIA S)
Remove the clamps and the hose. Apply both suction and pressure to the engine-side of the hose, and verify that air flows only toward that side. (Scheme 19) If air flows in both directions or not at all, replace the vacuum hose.
Scheme 19
VACUUM PUMP INSPECTION (MILLENIA S)
- Disconnect the vacuum hose from the power brake unit side of the vacuum pump and plug them.
- Disconnect the vacuum hose from the solenoid valve side of the vacuum pump and connect a vacuum gauge as shown in illustration. (Scheme 20)
- Under the conditions specified in the «VACUUM PUMP SPECIFICATIONS»(ref-91104-S09781152322004120600000) table, measure the vacuum using a vacuum gauge. If not as specified, replace the pump. VACUUM PUMP SPECIFICATIONS Condition Vacuum In Hg. (KPa) After Running Engine At 900 RPM For 20 Seconds 17.3 (58.7) After Running Engine At 1800 RPM For 20 Seconds 22.8 (77.3)
