Test AX: Engine Coolant Temperature And Engine Oil Temperature Correlation

PINPOINT TEST AX: ENGINE COOLANT TEMPERATURE AND ENGINE OIL TEMPERATURE CORRELATION

Flow Chart:

WARNING: Strict observance of posted speed limits and attention to driving conditions are mandatory when carrying out the road test. Failure to follow these instructions may result in personal injury.

This pinpoint test is intended to diagnose the following:
- low engine coolant level
- Cooling system flow restriction
- ECT sensor
- EOT sensor

-----------------------------------------------
AX1 : CHECK FOR AN ENGINE COOLANT LOSS OR AN ENGINE OVERHEATING CONCERN

- Carry out a visual inspection. Refer to the Cooling System, Engine Cooling, Inspection and Verification.
- Verify the pressure relief cap is capable of holding system pressure.
- Verify that the coolant and cooling system maintenance has been carried out as recommended.
- Is the engine overheating or loosing coolant?






-----------------------------------------------
AX2 : CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS)

- Retrieve and record all DTCs.
- Record the freeze frame data.
- Are there any other DTCs present?






-----------------------------------------------
AX3 : CHECK ECT OR EOT SENSOR FOR DAMAGE

- Inspect the ECT and EOT sensor and circuits at the sensor and PCM for the following:
- pinched, shorted, and corroded wiring and pins
- oil or water contamination
- crossed sensor wires
- contaminated or damaged sensor

- Is a concern present?






-----------------------------------------------
AX4 : CHECK FOR CORRECT ECT AND EOT SENSOR OPERATION

NOTE: Verify that no accessories are in use (engine block or oil heaters).

- Clear all the DTCs.
- Cold soak the vehicle at ambient temperature for a minimum of 10 hours.
- Ignition ON, engine OFF.
- Access the PCM and monitor the ECT PID.
- Access the PCM and monitor the EOT PID.
- Access the PCM and monitor the RPM PID.
- Access the PCM and monitor the MFDES PID.
- Record the ECT and EOT sensor temperature values.
- Drive the vehicle at an engine speed greater than 1,800 RPM and 15 mg/stroke MFDES for at least 15 minutes. Select the appropriate gear to achieve the operating conditions.
- Does the ECT PID and EOT PID temperature values change by a minimum of 6°C (10°F) from when the ignition ON, engine OFF valves were recorded?