What to Do When the Engine Fails to Shut Down?
2 Answers
Engine failure to shut down may be caused by incomplete power cut-off to the shutdown solenoid valve, key switch sticking, damage to the shutdown solenoid valve, or deformation of the lever. It could also be due to sticking of the unit pump or the engine governor rack sticking or deforming. Below are the steps to troubleshoot the engine shutdown issue: 1. Starting Circuit: Check that the starting circuit is properly powered and the ignition key switch is not sticking. 2. According to customer feedback and on-site testing, the roller operates without speed drop and manual shutdown is normal, which proves that the unit pumps in each cylinder are not sticking. 3. Shutdown Solenoid Valve: After replacing the shutdown solenoid valve with a new one using the correct installation method and testing with power, the engine still fails to shut down automatically. 5. Engine Stop Lever: If the engine stop lever feels insufficiently elastic when moved, it may indicate that the engine governor rack is sticking or deformed, causing damage to the shutdown solenoid valve and preventing the engine from shutting down automatically.
I encountered this situation last time and was really a bit panicked. Quickly shift to P gear and pull the handbrake to ensure safety first. Upon inspection, I found that the ignition switch return spring was stuck, and there was no noticeable rebound when turning the key. Another possibility is that the steering wheel lock is pressing against the ignition switch. Try turning the steering wheel left and right before pulling out the key. A short circuit is the most troublesome, especially for cars with modified anti-theft devices, as they are prone to this issue. If all else fails, you can temporarily disconnect the negative terminal of the battery, but some cars may lose window memory after power loss and require relearning. After using these emergency methods, it's best to have a professional mechanic check as soon as possible, as continuous operation can cause significant damage to the engine.
