# 2000 Maxima Computer reprogram



## Ran (Mar 3, 2005)

I have a 2000 Maxima that keeps getting a Lean Engine fault code, both LH and RH. I replaced the O2 sensors. I am told I should get my computer reprogramed with new software. Should this be covered under some kind of warranty -eg emisson control.


----------



## Ran (Mar 3, 2005)

*2000 maxima ECU software upgrade*

Talked to a former Nissan mechanic, I have a too lean condition (code 174 and 171). I replaced the 02 sensors. Now the mechanic says I probably need a software upgrade. Any idea what this software does.


----------



## am3rican (Feb 26, 2005)

RLee said:


> Talked to a former Nissan mechanic, I have a too lean condition (code 174 and 171). I replaced the 02 sensors. Now the mechanic says I probably need a software upgrade. Any idea what this software does.


Should be free to reprogram your ECM. So I wouldnt worry about it. Its covered under the Federal Emissions warranty. From what I comprehend, I could be wrong, the reprogram makes the whole emissions diagnosis process less stringent. This is related to the P0420 technical service bulletin I believe.


----------



## NoKTournAL (Feb 11, 2003)

RLee said:


> Talked to a former Nissan mechanic, I have a too lean condition (code 174 and 171). I replaced the 02 sensors. Now the mechanic says I probably need a software upgrade. Any idea what this software does.


Air Flow Meter.
Former Nissan mechanic ??

Thank god.

Only P0100 got reprogrammed. If you had P0420/430 reprogram done, then it is already updated.

BTW its 8/80K mi


----------



## Snichols (Nov 22, 2005)

*ECU 171 Fuel too lean 3.5L Pathfinder*

After cleaning air induction system, replacing fuel filter, cleaning fuel injectors, I still get 171 right fuel bank fuel lean code after a few miles. Is it a bad O2 sensor? I also use K&N filter which tends to push the limits on the system. 63K


----------



## Puppetmaster (Mar 28, 2005)

Snichols said:


> After cleaning air induction system, replacing fuel filter, cleaning fuel injectors, I still get 171 right fuel bank fuel lean code after a few miles. Is it a bad O2 sensor? I also use K&N filter which tends to push the limits on the system. 63K


The K&N shouldn't really have anything to do with it, unless the MAF has been affected. A bad O2 sensor is possible, try swapping out the upstream O2 sensor on Bank 1 (right bank or rear manifold) and see if that fixes it. 

FSM lists the following as possibilties: 

Intake air leaks
Heated oxygen sensor 1 (front)
Injectors
Exhaust gas leaks
Incorrect fuel pressure
Lack of fuel
Mass air flow sensor


----------



## Snichols (Nov 22, 2005)

*171 Too lean*

Thank you for your reply - my MAF sensor is fried and my mechanic says it is a result of the K&N --$565 + labor from Nissan who had told me the K&N was fine to use. It looks like I'm stuck to replace it and to go back to the conventional filter-loss of performance and milieage. Ideas appreciated.




Puppetmaster said:


> The K&N shouldn't really have anything to do with it, unless the MAF has been affected. A bad O2 sensor is possible, try swapping out the upstream O2 sensor on Bank 1 (right bank or rear manifold) and see if that fixes it.
> 
> FSM lists the following as possibilties:
> 
> ...


----------



## Puppetmaster (Mar 28, 2005)

Snichols said:


> Thank you for your reply - my MAF sensor is fried and my mechanic says it is a result of the K&N --$565 + labor from Nissan who had told me the K&N was fine to use. It looks like I'm stuck to replace it and to go back to the conventional filter-loss of performance and milieage. Ideas appreciated.


What year is your car? Your title says Pathfinder? Either way, check the part number on your current MAF and lemme know what it is. 

I'm not sure if this applies to the Pathfinder, but I'm just gonna post it anyways. 

Part number can be found here:










If you have a 2002 or later, with a MAF that is 22680-6N201 or 22680-AM600, you can do the following:

1. Buy the Nissan recommended MAF (part number 22680-AM600) for 400+ and do the install yourself. It takes less than 30 mins with the right tools. This is supposedly a pretty robust MAF. You may also be able to find these at junkyards for less than 150. 

2. Buy a MAF from a 2001 Maxima (22680-2Y001) for around $90, transfer the IAT thermistor from your existing MAF to the 2Y001 and it will work fine. If you do not transfer the IAT sensor, you will throw a code, but the car should run fine. 










If you have a 2000-2001, then just buy the 2Y001, replace yours and call it a day. 

Where to buy either of these for a decent price? Call Dave Burnette at South Point Nissan in Austin, TX. 1-888-254-6060. He will be able to give ya a good price as well as more technical input. A lot of us over at Maxima.Org get parts and advice from him. 

* Pics are not mine, they are from Jime at maxima.org.


----------



## Puppetmaster (Mar 28, 2005)

One more question, did you clean the K&N and then blow the MAF? Because typically it happens when the K&N is cleaned and re-oiled. The MAF doesn't seem to like excess oil. Most people I know just use the K&N for 50k miles, toss it, and get a new one. IMO, its not worth the risk, given these sensitive (crappy) MAFs that some of us have.


----------



## Snichols (Nov 22, 2005)

*MAF Number*

Thanks for your generous amount of time - Title says 2001 although Pathfinder is not stated specifically. Part number on car is 22680-4W000, dealer gives #22680-4W001 to replace at $560. Actually, the Check Engine Light has stayed off since the mechanic cleaned the sensor with a spray solvent (choke or brake). Also found a refurb for $189 +core- a bad idea?
Much thanks -Snichols



Puppetmaster said:


> What year is your car? Your title says Pathfinder? Either way, check the part number on your current MAF and lemme know what it is.
> 
> I'm not sure if this applies to the Pathfinder, but I'm just gonna post it anyways.
> 
> ...


----------



## Puppetmaster (Mar 28, 2005)

I forgot the cleaning option.  

Yes, sometimes cleaning the (suspected oil) off the MAF does help. If the codes stay off and the car runs fine after cleaning, then that would be all ya need to do.


----------

