What it means
Cylinder 2 pressure sensor above upper plausibility — open signal or short to B+. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The cylinder 2 pressure sensor measures combustion pressure so the engine control module can assess that cylinder's operation. This code sets when the sensor circuit reports a signal above the module's plausible range, which can happen with an open signal path or a wire shorted to battery voltage.
Common causes
Most likely first.
- Open signal line
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check engine light on
- Rough running or misfire
- Reduced engine power
- Hard starting
How to diagnose it
- Record freeze-frame data and check live data for cylinder 2 pressure to see whether the reading is stuck high or changes with engine operation.
- With the engine off, inspect the cylinder 2 sensor connector for moisture, corrosion, loose fit, or pushed-back pins that could interrupt the signal.
- Trace the cylinder 2 sensor wiring for chafing, pinching, or contact with a battery-positive feed, paying particular attention near hot or moving parts.
- With the code active, gently move the harness while watching the sensor reading to see whether the fault responds to movement.
- Check the signal, supply, and ground circuits against the manufacturer's specification to distinguish an open signal wire from a short to battery voltage.
Common fixes
- Secure or reroute wiring that is chafed, pinched, or contacting a power feed.
- Clean and dry the connector, then repair loose, corroded, or pushed-back terminals.
- Repair an open or shorted cylinder 2 sensor signal wire.
- Replace the cylinder 2 pressure sensor if its circuit checks pass but its signal remains implausibly high.
Can I keep driving?
Avoid hard acceleration and have the fault checked soon; a high or unreliable cylinder 2 pressure reading can cause rough running, misfire, hard starting, or reduced power. Stop if the engine runs severely rough or loses power in traffic.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.