P1400 Manifold differential pressure sensor circuit malfunction
Check Conditions:
a) 8 minutes or more have passed after starting the engine. Note that this is only if the engine coolant temperature is less than 0°C (32°F) when starting. Engine coolant temperature is higher than 45°C (113°F). Intake air temperature is higher than 0°C (32°F). Volumetric efficiency is between 30 and 55 percent.
Judgment Criteria:
Manifold differential pressure sensor output voltage has continued to be higher than 4.6 volts [corresponding to an absolute pressure of 118 kPa (17 psi) or higher] for 2 seconds, or manifold differential pressure sensor output voltage has continued to be lower than 0.1 volt [corresponding to an absolute pressure of 2.4 kPa (0.3 psi) or lower] for 2 seconds.
b) 8 minutes or more have passed after starting the engine. Note that this is only if the engine coolant temperature is less than 0°C (32°F) when starting. Engine coolant temperature is higher than 45°C (113°F). Intake air temperature is higher than 0°C (32°F). Volumetric efficiency is lower than 30 percent.
Judgment Criteria:
Manifold differential pressure sensor output voltage has continued to be higher than 4.2 volts [corresponding to an absolute pressure of 108 kPa (16 psi) or higher] for 2 seconds.
c) 8 minutes or more have passed after starting the engine. Note that this is only if the engine coolant temperature is less than 0°C (32°F) when starting. Engine coolant temperature is higher than 45°C (113°F). Intake air temperature is higher than 0°C (32°F). Volumetric efficiency is higher than 70 percent.
Judgment Criteria:
Manifold differential pressure sensor output voltage has continued to be lower than 1.8 volts [corresponding to an absolute pressure of 46 kPa (4.6 psi) or lower] for 2 seconds.
The most likely causes for this code to be set are:
- Manifold differential pressure sensor failed.
- Open or shorted manifold differential pressure sensor circuit, or loose connector.
- PCM failed.
Check Conditions:
a) 8 minutes or more have passed after starting the engine. Note that this is only if the engine coolant temperature is less than 0°C (32°F) when starting. Engine coolant temperature is higher than 45°C (113°F). Intake air temperature is higher than 0°C (32°F). Volumetric efficiency is between 30 and 55 percent.
Judgment Criteria:
Manifold differential pressure sensor output voltage has continued to be higher than 4.6 volts [corresponding to an absolute pressure of 118 kPa (17 psi) or higher] for 2 seconds, or manifold differential pressure sensor output voltage has continued to be lower than 0.1 volt [corresponding to an absolute pressure of 2.4 kPa (0.3 psi) or lower] for 2 seconds.
b) 8 minutes or more have passed after starting the engine. Note that this is only if the engine coolant temperature is less than 0°C (32°F) when starting. Engine coolant temperature is higher than 45°C (113°F). Intake air temperature is higher than 0°C (32°F). Volumetric efficiency is lower than 30 percent.
Judgment Criteria:
Manifold differential pressure sensor output voltage has continued to be higher than 4.2 volts [corresponding to an absolute pressure of 108 kPa (16 psi) or higher] for 2 seconds.
c) 8 minutes or more have passed after starting the engine. Note that this is only if the engine coolant temperature is less than 0°C (32°F) when starting. Engine coolant temperature is higher than 45°C (113°F). Intake air temperature is higher than 0°C (32°F). Volumetric efficiency is higher than 70 percent.
Judgment Criteria:
Manifold differential pressure sensor output voltage has continued to be lower than 1.8 volts [corresponding to an absolute pressure of 46 kPa (4.6 psi) or lower] for 2 seconds.
The most likely causes for this code to be set are:
- Manifold differential pressure sensor failed.
- Open or shorted manifold differential pressure sensor circuit, or loose connector.
- PCM failed.