P0343: the camshaft position sensor signal is reading too high
The camshaft position sensor tells the engine control unit exactly where the camshaft, the rotating shaft that opens and closes the valves, is at any instant, which the computer uses alongside the crankshaft signal to time each injection correctly. This code means the electrical signal from bank 1's sensor is reading higher than the range the computer will accept. With this signal out of range, the engine control unit falls back on a default assumption instead.
You might notice
- The engine may struggle to start, run roughly, or stall
- The engine warning light comes on
- camshaft position sensor
- — a sensor that tells the computer exactly where the camshaft is at any instant
- camshaft
- — the rotating shaft that opens and closes the engine's valves
- bank 1
- — the side of the engine that has cylinder number 1
What the code itself says
P0343 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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