Question

i have a code p0171 on my nissan sentra 2007

Answer 1

Check for an intake leak first, common problem on the Sentra were the intake gasket is bad. You can spray brake cleaner near the intake manifold while the car is running and see if there is an RPM change you will hear it go up and down if the RPM changes. Dont spray on hoses and wires, metal parts only

 

Possible causes

- Intake air leaks
- Faulty front heated oxygen sensor
- Ignition misfiring
- Faulty fuel injectors
- Exhaust gas leaks
- Incorrect fuel pressure
- Lack of fuel
- Faulty Mass Air Flow (MAF) sensor
- Incorrect Positive Crankcase Ventilation (PCV) hose connection