Symptoms of P0346
- Rough idle, shaking, or a stumble under acceleration.
- A flashing check-engine light during an active misfire.
- Power loss and higher fuel consumption.
Common causes of P0346
- Worn spark plugs, ignition coils, or plug wires.
- Fuel-delivery problems — injectors, pressure, or a lean/rich mixture.
- Vacuum leaks, low compression, or a mechanical fault in that cylinder.
Useful checks before replacing parts
- Compare Bank 2 cam signal timing, cam-crank correlation, VVT command and actual position, freeze-frame RPM, oil condition, and related cam timing codes.
- Inspect sensor mounting, target wheel condition, timing chain or belt condition, phaser behavior, wiring resistance, and connector integrity.
- Check whether the signal becomes implausible during startup, hot idle, acceleration, or VVT movement before replacing parts.
How serious is P0346, and can you keep driving?
- Urgency
- High when the lamp is flashing
- Safe to drive?
- A flashing check-engine light means stop — a steady one means drive gently and get it looked at.
This is the one code family where the lamp itself tells you the urgency. A steady light means the misfire was detected and logged. A flashing light means it is happening right now and is severe enough to be dumping raw fuel into the catalytic converter, which can overheat and be destroyed in minutes rather than months. Pull over, switch off, and get the car recovered rather than driving it on. A converter costs many times what a coil or a plug does.
Clearing P0346, and making it stay gone
Clearing P0346 with a scan tool switches the lamp off; it does not fix anything, and it throws away the freeze-frame snapshot the car saved when the fault set. That snapshot is the most useful diagnostic evidence you have, because it records the load, RPM and temperature at the moment the test failed. Read it before you erase it.
Left alone, the lamp goes out on its own once the monitor that failed runs and passes on three consecutive driving cycles. The code stays in history after that, which is how a workshop can still see it. Disconnecting the battery is not a shortcut — it clears the stored codes and every learned fuel-trim value with them, so the car relearns from scratch and the underlying fault simply sets the code again.
On vehicles from roughly 2010 onward there is also a permanent DTC, which no scan tool can erase at all. It clears only when the monitor genuinely passes. That is deliberate: it stops a code being wiped in the car park outside an emissions test.
What P0346 costs to put right
There is no honest single figure for P0346, and any page that gives you one is guessing. The code names a circuit or a failed monitor, not a part — the same code can be a chafed wire, a connector full of water, or the component itself, and those are three very different bills.
The number worth budgeting for is diagnostic time. An hour of it is almost always cheaper than the second part you buy after the first one does not fix it, and parts fitted on a guess are rarely refundable once installed. If you are getting a quote, ask what the diagnosis found rather than what is being replaced — a ignition / misfire fault traced to a specific cause is a repair, and a list of parts is a hopeful shopping list.
Questions people ask about P0346
What does P0346 mean?
P0346 points to a range or performance issue in Camshaft Position Sensor A circuit on Bank 2. The Bank 2 cam signal exists but is not plausible compared with crankshaft position or engine state.
Can I drive with P0346?
A flashing check-engine light means stop — a steady one means drive gently and get it looked at. This is the one code family where the lamp itself tells you the urgency. A steady light means the misfire was detected and logged. A flashing light means it is happening right now and is severe enough to be dumping raw fuel into the catalytic converter, which can overheat and be destroyed in minutes rather than months. Pull over, switch off, and get the car recovered rather than driving it on. A converter costs many times what a coil or a plug does.
What causes P0346?
The usual candidates are worn spark plugs, ignition coils, or plug wires; fuel-delivery problems — injectors, pressure, or a lean/rich mixture; vacuum leaks, low compression, or a mechanical fault in that cylinder. The code tells you which test failed, not which of those did it — that is what the checks on this page are for.
Will P0346 clear itself?
Left alone, the lamp goes out on its own once the monitor that failed runs and passes on three consecutive driving cycles. The code stays in history after that, which is how a workshop can still see it. Disconnecting the battery is not a shortcut — it clears the stored codes and every learned fuel-trim value with them, so the car relearns from scratch and the underlying fault simply sets the code again.
Does P0346 mean I need to replace a part?
Do not replace the Bank 2 cam sensor before checking cam timing, oil control, and signal plausibility.
How much does it cost to fix P0346?
There is no honest single figure for P0346, and any page that gives you one is guessing. The code names a circuit or a failed monitor, not a part — the same code can be a chafed wire, a connector full of water, or the component itself, and those are three very different bills.
Related OBD-II codes
These nearby ignition / misfire entries can help compare wording and pin down the fault area.