P0345
PowertrainCamshaft Position Sensor A Circuit Malfunction (Bank 2)
The camshaft position sensor on bank 2 tells the ECU exactly where the camshaft is in its rotation, so the engine knows when to fire each spark and squirt fuel. When that signal goes missing or turns ragged, the ECU loses track of the cam timing on that bank and starts guessing. That's why you get the warning light along with hard starting, a lumpy idle, or misfires. On a V6 or V8, bank 2 is the side furthest from cylinder one, which on a lot of transverse engines means it's the bank tucked against the bulkhead and a pain to reach.
ⓘ Information only. This page provides general educational information about fault code P0345. We do not assess the urgency or safety implications of any specific fault. That requires in-person diagnosis by a qualified mechanic. Full terms.
Recommended next steps
Whether a fault is urgent, drivable, or routine depends entirely on the cause on a specific vehicle, and that can only be determined by a qualified mechanic with diagnostic equipment. If a warning light is illuminated, the most reliable next step is professional diagnosis.
What does P0345 mean?
P0345 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Camshaft Position Sensor A Circuit Malfunction (Bank 2).
This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms commonly associated with this code
Symptoms that drivers often report alongside this code. Not all may apply to every case:
- • Engine warning light, sometimes flashing if there's an active misfire on that bank
- • Long crank or hard starting, worst first thing on a cold morning
- • Rough, shaky idle that smooths out as revs climb
- • Hesitation or a flat spot when you put your foot down
- • Misfires showing on the bank 2 cylinders specifically
- • Drop in performance, occasionally a stall at a junction or roundabout
Possible causes
Causes commonly associated with P0345, listed in approximate order of typical investigation. The actual cause on a specific vehicle can only be confirmed by professional diagnosis.
- 1. The bank 2 cam sensor has packed in, the most common cause and usually a cheap part
- 2. Wiring or connector trouble at the sensor, think chafed insulation, green corrosion in the plug, or a connector that's worked loose with engine vibration
- 3. Oil sat on the sensor tip from a leaking cam cover gasket, which is a classic on higher-mileage engines and fools the sensor into reading wrong
- 4. Stretched timing chain or a slipped belt throwing the cam timing out enough that the signal no longer lines up where the ECU expects it
- 5. A damaged reluctor ring or trigger wheel on the cam, less common but it does happen
- 6. Variable valve timing actuator playing up on bank 2, which can drag the cam position out of spec
- 7. ECM calibration or an internal module fault, rare and the last thing to suspect
How mechanics typically diagnose
A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training.
- 1. Pull the freeze frame data and check for other bank 2 codes sitting alongside it, misfire codes or a P0341 will steer you fast
- 2. Get eyes on the sensor connector and the short length of harness near it. Unplug it, look for oil inside the plug, bent pins, or corrosion, and give the wiring a wiggle while watching live data if you can
- 3. Check the oil level and condition. A leaking cam cover gasket dripping onto the sensor is a frequent culprit, and that needs sorting or you'll be back here in a month
- 4. Back-probe the sensor with a multimeter and compare voltage and resistance to the manufacturer figures. A two-wire mag sensor should show a resistance in the manual's range, a three-wire Hall type wants a steady reference voltage
- 5. Pull the sensor out and inspect the tip for oil, swarf, or physical damage. Clean it and refit if it looks contaminated rather than dead
- 6. If sensor and wiring check out, look at the timing. A swap test between the bank 1 and bank 2 sensors will tell you whether the fault follows the part or stays put on the bank
Common questions about P0345
If I clear the code, will it stay gone or just come back? +
Depends entirely on what set it. If it was a one-off glitch or a connector that's now reseated, clearing it might be the end of it. But if the sensor is dying or oil is sitting on the tip, the light will be back within a few drive cycles, sometimes the same journey. Clearing the code without fixing the cause is just resetting the messenger. If it returns, you've got a real fault, not a fluke.
What am I risking if I just leave it and keep driving? +
Worst case is the engine drops into limp mode or stalls on you at low speed, which is no fun pulling out of a junction. If P0345 is sitting alongside misfire codes, you're dumping unburned fuel into the exhaust and that can cook the catalytic converter, which turns a cheap sensor job into a much bigger bill. There's also a chance the root cause is timing chain stretch, and ignoring that on something like a VW or Audi V6 can end in valve damage. Don't sit on it for months.
How quickly do I actually need to sort this? +
Sooner rather than later, but it's not a tow-it-home emergency unless the car is stalling or in limp mode. If it starts and drives reasonably, book it in within a week or two and get the cause diagnosed properly. The urgency jumps right up the moment you see misfires or feel it stalling, because at that point you're risking the cat and possibly the timing. A loose connector is a ten-minute fix, so it's worth checking before you assume the worst.
Information only, not professional advice
The information on this page is provided for general guidance and educational purposes only. It is not a substitute for diagnosis or repair advice from a qualified mechanic. Always verify any fault before paying for repairs. carfaultcodes.co.uk accepts no liability for decisions made based on this information. Full terms →