What's the difference between P0345 and P0340?

They describe the same 'A' camshaft position sensor circuit fault on different banks. P0340 is Bank 1 (the side with cylinder number 1) and P0345 is Bank 2 (the other side). Diagnosis is identical; you just work on the Bank 2 sensor and its wiring.

Can I drive with a P0345 code?

Sometimes, but cautiously. Many engines keep running on the crankshaft signal with only hard starting or reduced power, while others may stall or fail to start once the cam signal is lost. Because the behavior is unpredictable, treat P0345 as something to diagnose promptly rather than ignore.

Is it always the sensor, or could it be the timing chain?

Not always the sensor. P0345 can also come from wiring damage, a contaminated sensor tip, a damaged reluctor ring, or a stretched timing chain that throws off cam-to-crank correlation. If the sensor and wiring test good, have the timing checked before replacing more parts.

Could low engine oil cause P0345?

It can on engines with variable valve timing. The camshaft sensor reads a phaser that is moved by oil pressure, so low or dirty oil can cause erratic cam timing and set the code. Checking oil level and condition is a cheap, worthwhile first step.

OBD-II trouble code

P0345: Camshaft Position Sensor 'A' Circuit (Bank 2)

The engine computer lost or received an unreliable signal from the 'A' camshaft position sensor on Bank 2. It can cause hard starting, stalling, or reduced power, and on some engines a no-start.

Quick facts

System: Powertrain
Category: Camshaft / Timing
Severity: Medium severity
Drivable: Usually safe to drive short-term
Repair cost range: $40 – $400
DIY difficulty: Intermediate DIY

What does P0345 mean?

The camshaft position (CMP) sensor reports the exact rotational position of the camshaft to the engine control module (ECM). The ECM combines that with the crankshaft position signal to know which cylinder is on its compression stroke, which lets it fire the correct fuel injector and ignition coil at the right moment and, on many engines, control variable valve timing. P0345 sets when the ECM sees a fault in the 'A' camshaft sensor circuit on Bank 2 — no signal, an intermittent signal, or a signal that doesn't correlate with the crankshaft.

Bank 2 is the side of the engine that does NOT contain cylinder number 1, so P0345 applies to V6, V8, and other V-configuration or some horizontally-opposed engines that have camshaft sensors on both banks. It is the Bank 2 counterpart to P0340, which covers the same 'A' camshaft sensor on Bank 1. The 'A' designation refers to a specific camshaft (typically the intake cam, or the sole cam on a single-cam-per-bank design) as defined by the manufacturer.

How much this affects driveability depends on the engine. Many vehicles can start and run using the crankshaft signal alone with a degraded-but-present strategy, so you may only notice hard starting, a stumble, or reduced power. On other engines, losing the camshaft signal prevents the ECM from synchronizing injection and spark, which can cause extended cranking or a no-start. Because the code can point to the sensor itself, its wiring, or a mechanical timing problem, it should be diagnosed rather than fixed by replacing the sensor on a guess.

Common causes

Failed Bank 2 'A' camshaft position sensor
Damaged, chafed, or corroded sensor wiring or connector
Metal debris or oil contamination on the sensor tip
Faulty reluctor/tone ring on the camshaft, or a damaged tooth
Stretched or jumped timing chain/belt throwing off cam-to-crank correlation
Low or dirty engine oil affecting a variable-valve-timing phaser the sensor reads
Wiring interference or a poor ground shared with other sensors

Symptoms

Check engine light is on
Hard starting or extended cranking, or a no-start on some engines
Engine stalling or stumbling
Reduced power or hesitation on acceleration
Rough idle or intermittent misfire feel
Possible drop in fuel economy

Diagnostic steps

1.Scan for all stored codes. Address any crankshaft position (P0335-series) or timing-correlation (P0016/P0018) codes together, since they interact with the cam signal.
2.Inspect the Bank 2 camshaft sensor connector and wiring for damage, oil intrusion, corrosion, or chafing.
3.Check engine oil level and condition — low or sludgy oil can disturb variable-valve-timing components the sensor monitors.
4.With a scan tool, watch the camshaft sensor signal (or RPM/sync data) while cranking to see whether the signal drops out.
5.Remove and inspect the sensor tip for metal debris or damage; inspect the reluctor/tone ring for chipped or missing teeth.
6.If the sensor and wiring test good but a cam-to-crank correlation fault remains, investigate timing chain/belt stretch or phaser problems before replacing parts.

Repair cost

$40 – $400

The camshaft position sensor itself is often $40 to $200 in parts, with 0.5 to 2 hours of labor depending on how buried it is. A straightforward sensor replacement is commonly $150 to $350 total. Wiring repairs are typically $50 to $200. Mechanical causes such as timing chain stretch cost substantially more and are diagnosed separately.

Estimate your repair

Run the numbers for your vehicle

Open the Repair Cost Estimator with camshaft position sensor replacement preselected. Adjust labor rate and vehicle category to fit your situation.

Estimate your repair cost

DIY vs shop

This is an intermediate DIY job. It usually involves diagnostic steps, specialty parts, and some careful work in tight spaces. If you have the tools and a service manual or trustworthy video for your specific vehicle, it is achievable in a weekend. Otherwise, a competent independent shop will be faster.