What it means
The cylinder 6 alternative-fuel injector control circuit has a voltage above the expected range. This indicates an electrical circuit fault, not necessarily an injector flow problem or short to battery.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The alternative-fuel injector for cylinder 6 is controlled by a dedicated module driver and circuit. P22EF sets when that circuit voltage is higher than expected, which signals an electrical fault but does not establish that the injector has a flow problem.
Common causes
Most likely first.
- Short to B+
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check engine light on
- Misfire or rough idle on the affected cylinder
- Increased fuel consumption
- Possible fuel smell or smoke from exhaust
How to diagnose it
- Save freeze-frame data and check live misfire data for cylinder 6 to see when the high-voltage fault appears.
- With the engine off, inspect the cylinder 6 alternative-fuel injector connector and harness for corrosion, loose pins, or a wire pinched against a power source.
- Compare the cylinder 6 control-circuit readings with the manufacturer's diagnostic information to confirm the high condition.
- With power isolated as specified by the manufacturer, check for an unintended connection between the control wire and B+.
- If wiring and connections pass, test the cylinder 6 injector and module driver using the manufacturer's procedures.
Common fixes
- Clean or repair corroded terminals at the cylinder 6 injector connector.
- Repair a cylinder 6 control wire pinched against a B+ source.
- Replace the cylinder 6 alternative-fuel injector if its electrical test fails.
- Repair or replace the control module only if its cylinder 6 driver is confirmed faulty.
Can I keep driving?
If the engine runs smoothly, limit driving and avoid heavy acceleration until the fault is diagnosed. A cylinder 6 misfire can increase emissions and fuel use, and continued misfiring may damage the exhaust catalyst.
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.