P0105: the manifold pressure sensor circuit has a fault
Some engines measure engine load with a manifold pressure sensor instead of, or alongside, an airflow sensor: it reads the pressure inside the intake manifold, which changes with how far the throttle is open and how hard the engine is working. This code means the electrical circuit for that sensor isn't behaving the way the engine control unit expects. It covers the wiring and connector as much as the sensor itself.
You might notice
- The engine warning light comes on
- The engine may idle unevenly or feel short of power
- manifold pressure sensor
- — a sensor that measures the pressure inside the intake manifold, which the computer uses to judge engine load
What the code itself says
P0105 is a powertrain (engine, gearbox and drive system) code, and the 0 after the letter means it is a generic code with a standard meaning.
Grouped here as: Engine running, fuelling and misfires — Air metering, fuelling, ignition, misfire, idle, boost, knock, oxygen sensors and the catalyst, all working together in the running engine. That grouping is ours, to help explain the code. The code's official family is the letter at the start.
This page is generic. Your car isn't.
A code on its own only tells you what the sensor saw, not what's actually wrong — and that changes next to your other codes. Read this one together with the rest of your scan and we'll work out what's really going on.
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