Carry Out The Key On Engine Running (KOER) On-Demand Self-Test: Purpose
WARNING: This page is about a different car, the 2008 Ford Pickup, 2008 Ford F550 Super Duty, 2008 Ford F450 Super Duty, and 2008 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The purpose of this test is to determine if the PCM has detected any fault conditions that would cause a performance concern while the engine is running. The KOER self-test carries out step tests on the high and low fuel pressure systems and the exhaust pressure system.
Step tests are PCM controlled tests where the PCM commands a specific exhaust pressure or fuel rail pressure (FRP) and then measures the result. If a predetermined threshold is not reached, a DTC is generated. This test can be carried out at any engine temperature.
Carry Out The KOER On-Demand Self-Test
NOTE:
Before carrying out the KOER On-Demand Self-Test make sure the high pressure oil passages are free of air. A recent repair to the system may allow air to enter the oil passages. To remove the air, drive the vehicle (with deceleration and acceleration cycles) at highway speeds for 32 km (20 miles).
- The self-test verifies the FRP, exhaust gas recirculation (EGR), and turbocharger systems performance.
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