What is fault code 16 in an Evinrude E-TEC engine "CPS intermittent loss of SYNC" and how to fix it.
Understanding the Crankshaft Position Sensor (CPS)
The CPS is crucial for monitoring the position and rotational speed of the crankshaft. This information is vital for the Engine Management Module (EMM) to control ignition timing and fuel injection accurately. An intermittent loss of synchronization between the EMM and CPS can lead to engine performance issues, making prompt diagnosis and repair essential.
Identifying Fault Code 16
Fault code 16 is recognized by specific behaviors in the engine's diagnostic LEDs and the engine's performance:
- LED 2 turns OFF during cranking, indicating the system is trying to establish a connection with the CPS.
- LED 3 turns ON when the engine is running, but synchronization losses occur. The EMM records 5 losses at RPMs below 2000 and 1 loss at RPMs above 2000.
Symptoms of CPS Synchronization Issues
- Difficulty starting the engine or complete failure to start.
- Unstable idling or stalling at low RPMs.
- Loss of power or surging at operational speeds.
- Possible misfires due to improper ignition timing.
Steps to Address Fault Code 16
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Check CPS Mounting: Ensure the CPS is securely mounted and positioned correctly. A loose or misaligned sensor can lead to intermittent signal losses.
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Measure Air Gap: The air gap between the CPS and the crankshaft should be within the range of 0.036 to 0.110 inches (1 to 2.8 mm), with a nominal value of 0.073 inches (1.85 mm). Use a feeler gauge to verify the gap and adjust as necessary.
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Test CPS Resistance: Measure the CPS resistance with a multimeter. The resistance should be approximately 560 Ω ± 10% at 77°F (25°C). A value outside this range suggests the CPS may be faulty and require replacement.
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Inspect Wiring and Connectors: Check for damaged wires or loose connectors that could interfere with the CPS signal. Repair or replace any faulty components.
