I have a 2001 Nissan Pathfinder SE 3.5.

Service Engine Light went on a month ago. I got it tested at Autozone and error of P0171 - system too lean (bank 1). Had it reset and now a month later, the light is back on and same error of P0171.

I've searched for P0171 errors on the forum, but did not find one for Pathfinder.

Also, is there any warranties under nissan that this would cover? I have 58k miles on the car.

Thanks!

Thanks for you help.

Tai

You want to make sure you dont have any vaccum leaks before you run out and buy the meter. If your intake boot after the meter was not secured properly or you had a vaccum line off it would throw the same code. Otherwise your are looking at the meter. Try one of our dealer sponsors. Really good prices on factory parts.

I was not able to find air flow meter part in nissanparts.org.
I emailed another place and they said the part is around $400?

Also another person suggested that the problem could be the fuel pump?
He said the air flow meter problem would cause an error code at both banks instead of just bank1?

Any thoughts?

Thanks again!

Tai

http://www.trademotion.com/par...gid=1

Not true I have seen a few of these have the code for only one bank and it still be the airflow meter. Thing is I use the consult to verify the other bank is running lean as well, just not lean enough to through a code.

Your first check should be for vaccum leaks before you get the meter.

Thanks for the link for the part also....it is a lot cheaper than any other place I looked at.

After filling up with Shell premium and ran a diagnostic at Autozone, the light went off, but I'm sure it will go back on shortly.

I will check for vacuum leak and let you know what I find next.

Thanks.

Do you have instructions on how to replace the airflow meter?

Also, do you guys recommend nissan air filters or can it be regular brands?

Thanks.

thanks

(I did buy a used Air Flow Meter(MAF) for $100 from a vehicle that had 55k miles on it.)

Thanks for everyone's input/help on this.

O2 Sensors check out fine, no Vaccum leak. Replacing the AF meter. How easy is that? Can I buy a used one from a wrecker?

J

I had a local mechanic friend installed it for me, but it should be pretty simple to install.

Same problem here. I went to Nissan and the parts guy told me that it isn't necessarily the fact that the filter is generic, but rather the material it's made of. He said Nissan sent out a TSB, informing the mechanics to not install any SILICONE air filter. The parts guy went on to say that he thought it was FRAM brand and maybe a few others that were made of that material. And it causes issues with the MAF.

So I bought the factory filter and will probably buy a new MAF sensor in the next couple of weeks.

-I checked the air flow rate with my scanner it is is within the factory perameters outlined in the FSM. At idle, the FSM range is 2.0-6.0 gm/s (I think). My Pathfinder is 2.46 gm/s.
-There is no noticable engine performance issues.
-Fuel efficiency is not out of the ordinary either. Averaging 16 city 20-21 highway. And it is winter time.

So other than the annoyance of the CEL on, is there even a reason to be overly concerned about replacing this thing right away?

Nissan/Infiniti Techs, do you have any feedback? Thanks.

Aaron

~Blessings.

I may be thinking incorrectly, however I've used electronic cleaner on the element in the maf of my 240 and got rid of an error code in it. Has anyone thought of trying to clean it?

If it is in fact silicone which is accumulating on the element in the air flow meter I would imaging some form of cleaner could safel remove it?

Just a thought...

do you know what's the value for the fuel trim for a new maf? stft and ltft?
thanks

The SEL finally came on a year later when my pathy started to be sluggish in the mornings or afternoon when the engine was completely cold. Codes for SEL were bank 1 lean and/or bank 1 and 2 lean. I had replaced the O2 sensors, fuel filter, cleaned fuel injectors, checked for air intake leaks as suggested and finally it came down to the MAF sensor, a $500 part! Cleaning MAF did not work. After reading forums I tried a Maxima MAF (part 22680-2Y001) for $110 at the dealer and it worked perfectly! Even replaced it myself...almost too easy. Performance is great! Went to AutoZone to have SEL reset.

first...check for any leaking hoses around your intake and throttle body. check the throttle body gasket.(if your getting bad gas mileage that could mean your sensor is bad)

third... make sure u check your maf sensor for any damage, or dirt and test it to see if its working properly. some symtoms of a bad maf are...hesitation. rough idle or engine is rough when cold. driving on the highway you will notice major lack of power and changes in speed....try using electronic cleaner and clean it out thouroughly...if defected u can go out and get a 01 nissan maxima maf sensor for like 120 bucks and it can be used for the 01 pathfinder.

I went through the same thing u went through and i did what i just posted and now my pathfinder is driving butter smooth and no ses lights for the past 2 months. the light goes out on its own

good luck

I miss read my code and bought it and it turned out that I needed a O2 sensor and not a maf.
It's BRAND new, never installed. I have pictures.
$75 + free shipping.
Just email me. body80@yahoo.com

Modified by body80 at 12:45 AM 12/4/2008

Followed instructions on changing MAF and cleared out the codes. Well, here is the problem. After I replaced the sensor, the engine runs rough in idle, and sometimes dies while it is parked. Do I need to reset something here? BTW, I only replaced MAF itself. I am going to try the whole unit including air tube for the next step.

Any ideas?

Thanks,