P0340 Code: Meaning, Symptoms, Causes & Fixes
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Causes ranked by likelihood
| Cause | Likelihood | DIY difficulty |
|---|---|---|
| Failed camshaft position sensor — Most common cause. Inexpensive part. | Most likely | 3/5 |
| Damaged sensor wiring — Heat-damaged connector or harness. | Possible | 3/5 |
| Stretched timing chain — Causes incorrect cam position relative to crank. | Less likely | 3/5 |
Symptoms of P0340
- Hard starting
- Stalling
- No-start
- CEL
How to diagnose P0340
- Confirm the code. Read P0340 with an OBD-II scanner and note the freeze-frame data (speed, temperature, load) recorded when it set.
- Check for companion codes. Look for other stored or pending codes such as P0341, P0335 — they often point to one shared root cause.
- Check: Damaged sensor wiring. Heat-damaged connector or harness.
- Check: Failed camshaft position sensor. Most common cause. Inexpensive part.
- Check: Stretched timing chain. Causes incorrect cam position relative to crank.
- Clear and verify. After the repair, clear the code and complete a full drive cycle to confirm P0340 does not return.
Can I drive with P0340?
No — engine may stall or fail to start. Tow if needed.
Related codes
Related symptoms
Frequently asked questions
What does P0340 mean?
P0340 means camshaft position sensor circuit malfunction. P0340 means the ECU isn't getting a proper signal from the camshaft position sensor. Usually the sensor itself has failed, but wiring and timing chain issues can also trigger it.
Can I drive with code P0340?
No — engine may stall or fail to start. Tow if needed.
What is the most common cause of P0340?
Failed camshaft position sensor — Most common cause. Inexpensive part.
What are the symptoms of P0340?
Hard starting, Stalling, No-start, CEL.
How much does it cost to fix P0340?
A typical shop repair range is $100–$500, depending on which cause it turns out to be. Cheaper causes such as stretched timing chain should be ruled out first.