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P0366 – Camshaft Position Sensor B Circuit Range/Performance (Bank 1) (OBD2)

P0366 means "Camshaft Position Sensor B Circuit Range/Performance (Bank 1)". The camshaft position sensor signal is electrically present but implausible: it does not match what the control unit expects for the current operating conditions or from other sensors. This is a performance fault, not a broken wire.

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P0366 quick summary

Fault codeP0366
MeaningCamshaft Position Sensor B Circuit Range/Performance (Bank 1)
SystemPowertrain (Engine & Transmission)
VehiclesGeneric OBD2
SeverityMedium
Can I drive?Usually yes, but expect longer cranking, less power and possibly limp mode. If the code appears together with timing correlation codes or a rattling chain, stop driving until the timing has been checked.
Repair cost€25 – €300

How the camshaft position sensor works

The camshaft position sensor tells the engine control unit which cylinder is on its compression stroke and, on engines with variable valve timing, the actual camshaft position.

The crankshaft turns twice for every turn of the camshaft, so the crankshaft signal alone cannot tell whether a piston at top dead centre is on its compression or exhaust stroke. The camshaft sensor solves this by reading a trigger wheel or special lobes on the camshaft. Most modern camshaft sensors are Hall sensors with a 5 V or 12 V supply.

Engines with variable valve timing often have one sensor per camshaft – intake (A) and exhaust (B), on V engines per bank. The control unit compares camshaft and crankshaft signals to measure the actual camshaft adjustment.

If the camshaft signal is lost, many engines still start, but it takes longer because the control unit has to guess the firing order. Power may be reduced and variable valve timing is switched off. Causes include a failed sensor, wiring problems, oil in the connector, and – importantly – a stretched or jumped timing chain or belt.

Bank 1 is the side of the engine that contains cylinder 1. In-line engines (three, four, five or six cylinders in a row) have only bank 1.

On VAG vehicles (VW, Audi, Škoda, Seat, Cupra), VCDS and older VAG testers can show this code as the five-digit VAG code 16750 (P0366). Both numbers mean the same fault.

Symptoms of P0366

  • Long cranking before the engine starts
  • Check Engine light on
  • Reduced power, limp mode
  • Rough idle or occasional stalling
  • Higher fuel consumption

Most common causes of P0366 (most likely first)

Mechanic's Pro Tip

Swap the intake and exhaust camshaft sensors (if they are identical) and clear the codes. If the code moves from sensor A to sensor B, the sensor is faulty; if it stays, look at wiring or timing.

  1. 1.Camshaft position sensor worn, contaminated or out of calibration

    Most likely

    The signal drifts slowly, so it is still within the electrical limits but wrong.

  2. 2.Mechanical problem in the system the camshaft position sensor measures or controls

    For example a leak, a sticking part or a restriction that really changes the measured value.

  3. 3.High resistance in a connector or ground

    Corrosion causes a voltage drop that shifts the reading.

  4. 4.Failed camshaft position sensor

    Hall sensors fail internally, often from heat.

  5. 5.Stretched or jumped timing chain/belt

    Changes the relationship between camshaft and crankshaft signals.

  6. 6.Damaged trigger wheel

    A loose, bent or wrongly fitted trigger wheel on the camshaft.

Step-by-step diagnostic guide

  1. 1

    Read codes

    Read all codes. Correlation codes such as P0016–P0019 alongside the sensor code point to timing chain or belt problems rather than the sensor.

  2. 2

    Compare live data with expected values

    Read the camshaft position sensor values in live data and compare them with related readings (engine speed, load, temperature or pressure) and with the specification. A value that is electrically fine but wrong for the conditions confirms a performance fault – then check the mechanical side before replacing the part.

  3. 3

    Inspect connector and O-ring

    Check the connector for oil and corrosion and the sensor O-ring for leaks.

  4. 4

    Check supply, ground and signal

    With the ignition on, check the supply and ground; while cranking, check that the signal switches.

    Multimeter: Supply typically 5 V or 12 V; signal switching between about 0 V and the supply voltage.

  5. 5

    Compare with the crankshaft signal

    On an oscilloscope, display camshaft and crankshaft signals together and compare the pattern with a known-good reference to rule out timing problems.

  6. 6

    Replace and verify

    Replace the sensor or fix the wiring, clear codes and confirm that the engine starts quickly and the code does not return.

Frequently asked questions

Can I keep driving with P0366?

Usually yes, but expect longer cranking, less power and possibly limp mode. If the code appears together with timing correlation codes or a rattling chain, stop driving until the timing has been checked.

How much does it cost to fix P0366?

Typical repair costs are 25 € – 300 €, depending on the cause and the vehicle. The most common fixes are: camshaft position sensor worn, contaminated or out of calibration; mechanical problem in the system the camshaft position sensor measures or controls; high resistance in a connector or ground. Always confirm the cause with the tests above before buying parts.

Will a bad camshaft sensor stop the engine?

Usually not while running, but it can cause longer cranking, rough running and limp mode. Some engines will not start at all without the camshaft signal.

Can a timing chain cause camshaft sensor codes?

Yes. A stretched chain or jumped belt changes the camshaft position, which can set sensor range/performance or correlation codes even with a healthy sensor.

What is the difference between P0366 and similar codes?

P0366 belongs to a group of codes for the same component that differ in the type or location of the fault: P0348 – Camshaft Position Sensor A Circuit High Input (Bank 2); P0349 – Camshaft Position Sensor A Circuit Intermittent (Bank 2); P0365 – Camshaft Position Sensor B Circuit (Bank 1); P0367 – Camshaft Position Sensor B Circuit Low Input (Bank 1); P0368 – Camshaft Position Sensor B Circuit High Input (Bank 1); P0369 – Camshaft Position Sensor B Circuit Intermittent (Bank 1). The tests on this page apply to the whole group; the type of fault tells you where to start.

Related fault codes

This guide is for information only. Working on vehicles can be dangerous — if you are unsure, have the car checked by a qualified mechanic. Values can differ between model years; always check the manufacturer's repair information.