P1151 FORD Lack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Lean Bank 2

Possible causes
– Faulty Oxygen Sensor
– Fuel pressure high or low
– MAF sensor dirty/defective
– Vacuum leak on engine
– Leaking fuel injector or fuel pressure regulator
– Faulty Powertrain Control Module
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P1151 FORD OBD Code Description