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Engine Controls - System/component Tests: Diagnosis Toyota Camry XV10

Testing & Diagnostics 2 illustrations ~305 words

OXYGEN SENSOR FEEDBACK VOLTAGE TEST

  1. Warm engine to normal operating temperature. Connect analog-type voltmeter to engine check connector "VF1" (or "VF") and "E1" terminals. (Scheme 121) Perform procedures listed in (Scheme 122).
  2. California models are also equipped with a sub-oxygen sensor.

Note. Codes No. 21, 25, 26 and 27 are Oxygen (O2) sensor circuit codes. Also check for coolant temperature sensor Code No. 22. Faulty coolant temperature sensor could cause faulty O2 sensor readings.

Scheme 121

Scheme 121
Scheme 121

Scheme 122

Scheme 122
Scheme 122

System Test

  1. Ensure modulator filter is clean and in good condition prior to performing test. Clean filter with compressed air. Disconnect vacuum hose from EGR valve.
  2. Using a "T" connector, connect a vacuum gauge in EGR valve vacuum line. Ensure engine starts and runs smoothly at idle. This ensures proper seating of EGR valve.
  3. The Bimetallic Vacuum Switching Valve (BVSV) and EGR modulator can be checked with engine coolant temperature less than minimum temperature and specified engine RPM in accordance with application. See «EGR SPECIFICATIONS»(ref-21027-S29758586932001010300000) table.
  4. Operate engine with engine coolant temperature less than minimum temperature and specified RPM. No vacuum reading should be obtained when operated with engine coolant temperature less than minimum temperature.
  5. Operate engine at normal operating temperature and specified RPM. See «EGR SPECIFICATIONS»(ref-21027-S29758586932001010300000) table. A low vacuum reading should be obtained.
  6. Disconnect hose from the "R" port of EGR vacuum modulator. see scheme 31
  7. Using additional hose, connect "R" port directly to intake manifold. High vacuum reading should be obtained at specified engine RPM. See «EGR SPECIFICATIONS»(ref-21027-S29758586932001010300000) table. NOTE: Engine should misfire due to large amounts of exhaust gas being injected into intake manifold.
  8. To check EGR valve, apply vacuum directly to EGR valve with engine idling. Engine should run rough or stall. If system did not operate as described, each component should be tested.
Model TypeMinimum TemperatureEngine RPM
2.0L113°F (45°C)2500
2.5L104°F (40°C)(1) 2500
(1) Check at 3500 RPM with hose from EGR to manifold.
(1)Check at 3500 RPM with hose from EGR to manifold.

EGR SPECIFICATIONS

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