P0340 on a Nissan Altima
P0340 means camshaft Position Sensor A Circuit Malfunction (Bank 1). On the Altima, a few causes come up far more than others.
What P0340 usually means on a Altima
P0340 indicates a problem in the Altima's camshaft position sensor circuit, which the ECU uses for timing and fuel/spark synchronization. On these engines it can cause hard starting, stalling, or intermittent no-starts, sometimes when the engine is hot. The sensor itself or its connector and wiring is the typical fault. It is a common, relatively inexpensive sensor to replace once confirmed.
Most common causes on the Altima
- Failed camshaft position sensor
Heat-related sensor failure is common and can cause hot-start problems on these engines.
- Wiring or connector fault
A chafed or corroded connector interrupts the signal.
- Crank/cam correlation issue
Timing-chain stretch on high-mileage engines can throw off cam timing and set the code.
What P0340 costs to fix on a Altima
The cam sensor is a modest part and generally accessible on the Altima, keeping this among the cheaper sensor repairs. Inspect the connector and wiring before replacing the sensor. If a stretched timing chain is behind it, the repair becomes far more involved.
Year, engine and mileage change the answer. Start a case and Redline weighs these causes against what your car shows, then names the check that would settle it.
Other codes on the Nissan Altima
Related symptoms
Nissan Altima problems & recalls by year
Based on widely reported patterns for this model; individual causes vary by year, engine and history. Generic P0340 behavior is covered on the main P0340 page. Confirm with a scan tool before buying parts.
P0340 on your Altima?
Every problem becomes a Case. Tell Redline what your Altima is doing: it shows what the evidence supports, what’s still missing, and what to check next, before you approve a repair.
“Inner pad ~1 mm. Outer pad 3 mm.”
Next: check the slide pins move freely before buying parts.