P1150moderate severityPowertrain
Lack of HO2S Switch — Adaptive Fuel at Limit (Bank 2)
on 2004 Ford Freestar 3.9L V6 · FWD
What this code means
The upstream heated oxygen sensor on Bank 2 is not switching properly, and the adaptive fuel strategy has reached its correction limit on Bank 2.
Symptoms
- Check Engine Light
- Poor fuel economy
- Rough idle
- Failed emissions
Common causes
- Large vacuum leak affecting Bank 2
- Faulty O2 sensor Bank 2
- Exhaust leak near Bank 2 sensor
- Fuel delivery issue Bank 2
Diagnostic steps
- Check for vacuum leaks on Bank 2 side
- Monitor O2 sensor switching
- Check fuel pressure
- Inspect exhaust for leaks
Repair notes
Repair vacuum or exhaust leaks. Replace O2 sensor if not switching.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1