What it means
The control module monitors the signal from fuel pressure sensor A for consistency. It sets this code when the signal becomes intermittent or changes erratically beyond the expected limits.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Fuel pressure sensor A provides a changing signal that the control module checks for continuity. This code sets when that signal drops out or changes erratically, often because vibration is interrupting contact at the connector or harness.
Common causes
Most likely first.
- Connector loose or corroded
- Connector with intermittent contact under vibration
- Harness routed against vibrating component
Symptoms
- Check engine light on
- Hard start, no start, or stalling under load
- Power loss especially at high load or rpm
- Possible long cranking time
How to diagnose it
- Review freeze-frame data and graph sensor A's live signal to see whether it drops out or jumps while pressure demand changes.
- Inspect sensor A's connector for looseness, corrosion, or damaged terminals, then check whether the harness is routed against a vibrating or moving part.
- With the engine operating only where safe, gently move the harness near sensor A while watching live data for signal interruptions.
- Check the signal, supply, and ground connections for intermittent opens or poor contact using the manufacturer's test procedure.
- If wiring remains stable, test sensor A's response against the manufacturer's specifications under the conditions that trigger the code.
Common fixes
- Reconnect and secure the sensor A connector.
- Clean or repair corroded or loose connector terminals.
- Reroute and secure wiring away from vibration, heat, or rubbing points.
- Repair an intermittent open or damaged section of the sensor A harness.
- Replace sensor A if its signal remains erratic with stable wiring and connections.
Can I keep driving?
Because the fault can come and go, fuel pressure readings may become unreliable without warning. Avoid demanding acceleration and stop driving if the engine stalls or loses power.
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.