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Jay
Jay, Nissan Technician
Category: Nissan
Satisfied Customers: 19266
Experience:  20+yrs experience with Nissan & Infiniti Trained & Certified.Currently still working for Dealer
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I have error code on my Nissian Frontier just had my oil

Customer Question

I have error code on my Nissian Frontier just had my oil change last week
Submitted: 1 year ago.
Category: Nissan
Expert:  Jay replied 1 year ago.

Hello my name is ***** ***** thank you for your question.

What error code are you getting?

Customer: replied 1 year ago.
P0171
Customer: replied 1 year ago.
Waiting for answer
Expert:  Jay replied 1 year ago.

Thank you.. That is a Fuel System lean code.

This is normally caused by a MAF sensor that is no longer metering air properly. When it doesn't meter air properly it normally causes the truck to run lean. I would recommend you have it checked, it's fairly easy if you have access to a scanner.

Do you have a cold air intake or K&N air filter on the truck?

Please give me time to type..

Expert:  Jay replied 1 year ago.

Also do you use Regular fuel grade?

Customer: replied 1 year ago.
Customer: replied 1 year ago.
Shell or Chevron
Expert:  Jay replied 1 year ago.

Yes, you use Regular? or Yes you have a Cold Air Intake or K&N air filter?

Customer: replied 1 year ago.
I use Regular gas
Customer: replied 1 year ago.
What is k&N filter
Expert:  Jay replied 1 year ago.

Regular and Plus ( middle grade ) since around October have had Ethanol added to the fuel from the fuel manufactures. They do this all around the country for the winter months. When you have Ethanol in the fuel it acts like Oxygen. So that also tends to runs cars lean and cause allot of false codes this time of year. I always like to suggest to use Super / Premium fuel. The octane level is so high that it does not need to be treated. Plus Premium is about the price of Regular in the summer if not cheaper right now.

Customer: replied 1 year ago.
What needs to be corrected to have engine
Come off for that code?
Expert:  Jay replied 1 year ago.

If you don't know what a K&N air filter that is good. They don't work in these cars anyway.

The best thing I would suggest is to run this fuel tank to almost empty. Then fill up with premium and clear the code. If the code returns, then I would have the MAF sensor checked to see if its metering air properly. If is not metering air properly, then please replace the MAF sensor with one from the dealer. After Market MAF sensors never work right. If you do get a After Market MAF sensor that does meter properly, it normally flat lines 02 sensor operations. So please when it comes to electrical parts. Stick with the dealer.

That is my suggestion to what you want to do to resolve your code. Fuel, then check MAF sensor.

Do you have any more questions on this?

Expert:  Jay replied 1 year ago.

it is very common to see fuel system lean codes due to the type of fuel this time of year.

Simply changing the fuel to premium could resolve the issue.

Expert:  Jay replied 1 year ago.

Any more questions on this?

Expert:  Jay replied 1 year ago.

Hello?

Customer: replied 1 year ago.
What is Maf sensor
Expert:  Jay replied 1 year ago.

MAF = Mass Air Flow .. This is what reads the air coming into the engine so the computer can add the proper fuel mixture to the air coming into the engine so it has a 50/50 mixture. MAF sensors fail 2 ways.

1st they meter air incorrectly so it confuses the computer as to how much air is coming into the engine so it can cause a rich or lean condition which can of course cause a lean or rich code. Replacing the MAF sensor with one from the dealer and clearing the corrective learning and performing a idle relearn will resolve the issue.

2nd the MAF sensor sets a MAF sensor code indicating it has fails. But that would be a cut and dry issue.

Since you have a fuel system lean code, before I would suggest replacing any parts I would rather you simply just try premium fuel. As I was saying it's very common to see fuel system lean codes and misfire codes due to the Ethanol in the fuel right now.

To clear the code yourself all you need to do is disconnect the negative battery cable for 15 mins.

I would do that after you run the tank low and fill it with premium.

Then if the code returns have the MAF sensor checked to see if it's metering air properly and needs to be replaced.

Expert:  Jay replied 1 year ago.

If you have any more questions on this, please feel free to ask.

If not, and you're satisfied with my help, please Rate me. That is how I get credit for my work.

I hope I have provided you with Excellent Service.

Thanks Jay!