P2028
EVAP Fuel Vapor Temperature Sensor Circuit Intermittent
Evaporative emissions (EVAP)
Generic OBD-II
Low
What it means
P2028 means the signal from the EVAP fuel vapor temperature sensor is intermittent or erratic. This sensor helps the EVAP system monitor fuel-vapor conditions for emissions control. It is an emissions-only fault — the engine runs normally — so the practical effect is the warning light and a possibly incomplete emissions readiness monitor.
Low
Can I keep driving? Safe to drive — this EVAP sensor fault does not affect how the engine runs; it mainly turns on the warning light and can block emissions readiness.
Common symptoms
What you'll notice
- Check-engine light on
- EVAP monitor may not complete (fails an emissions readiness check)
- Usually no noticeable change in how the vehicle drives
Common causes
Most likely first
- Intermittent open, short, or loose connection in the vapor temperature sensor wiringLikely
- Corroded or backed-out connector pin at the sensorCommon
- Failed EVAP fuel vapor temperature sensorCommon
- Poor ground or reference-voltage supply to the sensorLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and wiggle-test the vapor temperature sensor connector and harness while watching live data.
- Inspect the connector for corrosion, spread pins, or moisture and repair as needed.
- Check the sensor's reference voltage and ground for dropouts.
- Replace the EVAP fuel vapor temperature sensor if the signal is intermittent. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P2028?+
Yes. It is an emissions-monitoring sensor fault with no effect on drivability, though it should be repaired to pass emissions testing.
Can I just clear P2028?+
You can, but because the fault is intermittent it will return until the wiring or sensor problem is fixed.
Related codes
Often seen with P2028
Read & clear P2028 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX