Fault code P0106 – a step-by-step guide to diagnosing and fixing it

The P0106 code is triggered when the powertrain control module (PCM) determines that the voltage output in the intake manifold absolute pressure sensor (MAP) circuit is abnormal. The car's MAP sensor is used to monitor the engine’s load. When the manifold pressure changes with the load, the device transmits a voltage signal, informing the PCM. The voltage should be between 1V to 1.5V at idle speed and roughly 4.5V at full throttle. If this signal varies significantly and the PCM doesn’t detect a corresponding change in the throttle angle, RPM or EGR flow, it registers this DTC.

• Water or dirt getting into the connector of the MAP sensor causing the contacts to corrode and a poor electrical connection. This can occur if the component is loose.
• Damage to the power supply cable’s insulation sheath, causing a short or open circuit.
• Electromagnetic interference due to proximity to high-voltage wires, the car alternator or car ignition coils.
• Leaks in the intake system or MAP vacuum hose, resulting from loose clamps, broken seals, thermal damage, cracking or wear.
• A malfunctioning device. It’s possible that there are faults with the internal components of the device.
• A clogged air filter, leading to a reduced air flow. If the air can’t pass through the dirty filter, the manifold pressure will be lower than normal.
• An overheating engine, causing valve damage and thereby reducing the compression levels in the cylinders.
• A low battery charge, affecting the power supplied to the car’s electronic components.

• A loss of engine power
• Poor or erratic acceleration
• A rough idle
• Excessive smoke or a strong fuel smell coming from the exhaust system
• Reduced fuel efficiency
• Carbon-fouled spark plugs

• The first step for repairing your vehicle is to diagnose the fault through visual inspections and a diagnostic scan. Using an OBD2 scanner, you can check the DTCs and freeze frame data registered by the vehicle’s onboard computer. Certain codes indicate specific causes, such as “P2279” which indicates that there is a leak somewhere in the intake air system. Once you have read through and deciphered this information, clear the check engine light.
• Inspect the wiring and power cable for signs of damage, corrosion or disconnection. Installing a new cable should restore the power supply to the sensor if it is the cause of the problem. Replace parts with visible defects and check the electrical connector to the device. It may be possible to restore the conductivity of the connector contacts by cleaning them and treating them with specialised products. After replacing wires, do a test drive to see whether or not the DTC reappears.
• You can measure the voltage of both the wires and the MAP sensor using a multimeter to see whether there is a problem with the connection or an internal fault. Compare the readings with the normal output range. The monitoring device can be tested further with a vacuum pump. To do this, apply 20 inches of pressure while the engine is switched off. If the voltage doesn’t drop, check the hose and passages for blockages.
• It may also be necessary to measure the battery charge.
• Make sure that the intake system is airtight, checking for leaks and cracks in the hose and ducts, as well as for loose or missing clamps. Resealing the system may involve replacing seals, pipes or hoses, and tightening fasteners.
• Upon inspection, buy a new air filter if necessary.The replacement interval for this component is usually between 12,000 to 15,000 miles.
• Examine and clean the throttle valve. Removing contaminants should unclog it, helping the parts to move easily and ensuring that it seals properly.