Recently had a bunch of work engine work done related to keeping oil and coolant fluids where they should be... valve stem seals, gaskets, spark plugs, etc.
Now it runs better than before, but P0171 and P0174 codes, Bank 01 System Too Lean, and Bank 02 System Too Lean, Confirmed.
http://engine-codes.com/p0171_chevrolet.html
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
"If the P0171 is combined with the P0174 code, it's very likely that the problem is caused by an intake leak. If there are no intake leaks, the next step is to replaced the air filter and clean the air flow meter."
This makes it sound easy to check for an intake leak?? Anybody have a good procedure for this?
From this list makes it sound like these codes could mean anything... Too much air or not enough fuel, for any possible reason.
My O2 sensors are new within a couple months so I doubt they went bad immediately. If it were misfiring it would be noticeable, and it should throw other codes, so I doubt that. I just had the injectors thoroughly cleaned. How can I rule out fuel pressure and MAF? What other symptoms would happen with incorrect PCV ? This all sounds like wild goose chase and takes me back to the Intake leak...
Now it runs better than before, but P0171 and P0174 codes, Bank 01 System Too Lean, and Bank 02 System Too Lean, Confirmed.
http://engine-codes.com/p0171_chevrolet.html
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
"If the P0171 is combined with the P0174 code, it's very likely that the problem is caused by an intake leak. If there are no intake leaks, the next step is to replaced the air filter and clean the air flow meter."
This makes it sound easy to check for an intake leak?? Anybody have a good procedure for this?
From this list makes it sound like these codes could mean anything... Too much air or not enough fuel, for any possible reason.
My O2 sensors are new within a couple months so I doubt they went bad immediately. If it were misfiring it would be noticeable, and it should throw other codes, so I doubt that. I just had the injectors thoroughly cleaned. How can I rule out fuel pressure and MAF? What other symptoms would happen with incorrect PCV ? This all sounds like wild goose chase and takes me back to the Intake leak...
