Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble getting a clear signal from a sensor that checks the hose letting air out of the engine. It's like trying to listen to a radio station that keeps cutting in and out.
The engine control module (ECM) is detecting an intermittent or erratic signal from the crankcase ventilation hose connection sensor, which monitors the flow of gases from the crankcase.
The P04E4 code indicates that the signal from the crankcase ventilation hose connection sensor is not stable. This sensor is responsible for ensuring that the gases from the crankcase are properly vented back into the intake system to be burned, reducing emissions. An erratic signal can affect engine performance and emissions control.
• Check Engine Light is on
• Poor engine performance
• Increased emissions
• Faulty crankcase ventilation hose connection sensor
• Damaged or corroded wiring or connectors
• Vacuum leaks in the crankcase ventilation system
Crankcase: The part of the engine that holds the crankshaft.
PCV: Positive Crankcase Ventilation, a system that recirculates gases from the crankcase back into the engine.
• Use an OBD-II scanner to confirm the code.
• Inspect the crankcase ventilation hose and sensor for damage.
• Check the wiring and connectors for corrosion or damage.
• Replace the crankcase ventilation hose connection sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Fix any vacuum leaks in the system.
• OBD-II scanner
• Multimeter
• Vacuum gauge
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Dodge Ram
• Regular maintenance of the PCV system
• Inspect hoses and connections periodically
• Ensure proper installation of sensors
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if you're unsure.
• Regularly check and maintain your vehicle's PCV system.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has become more common as vehicles have become more reliant on sensors for emissions control.
Moderate – It should be addressed soon to prevent potential engine performance issues.
Ignoring emissions-related issues can lead to increased pollution and may be illegal in some regions.
• Engine at operating temperature
• Vehicle in park or neutral
The crankcase ventilation hose connection sensor is typically located near the engine, connected to the crankcase ventilation hose.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to poor engine performance and increased emissions, which may cause your vehicle to fail an emissions test.
Q: Can I drive with this code?
A: While the vehicle may still be drivable, it's best to address the issue promptly to avoid further complications.
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