p0171 error and other problems ?

[xeonzerox2]

ill try to add as much detail as I possibly can, i have a Nissan Micra S 1.0l auto, this was recently purchased as my first car, but long story short, i decided to check on a diagnostic tool to see what the engine light was on for, i was told its nothing to worry about as it was checked by a garage in the local area, but it turned out to be P0171 - System Too Lean (Bank 1) (this was on a obd2 reader i got off eBay by the way) after extensive googling it was down to either the MAF or Lambda or other things, anyway, after getting a friend who knows a bit about cars etc.. having a go in the car he only said it seems to rev high before changing gear, it seems to be in limp home / limp-in mode, and this is the same after clearing the error code, (no engine light has reappeared at the moment) also there has been a few occasions where it has shifted up a gear and sometime (most times not),just to note im not flooring the pedal before you ask, i tried slow and steadily pushing in the accelerator and flooring it, I also saw on Google that people disconnect the MAF and apparently the car runs normal while disconnected, i did this and there was no change so I assumed it was not the cause, i have not tested either lambda sensors as I don't have the facilities

my questions are

will the error cause the car to be in limp home mode or cause any real performance issues
is the auto transmission or part of it on the way out ?
(if so how to diagnose it )

im not great with cars but can do some checks and replace parts etc...

im really stuck for what to do next, what shall i test and how, and its it time to call it quits and sell / scrap it as i really don't know ( seems drastic) keeping in mind that i cant fork out cash for tons of replacement parts unless its really in dire need to changing, ( low wages etc...)

im willing to take any suggestions and answer any questions just let me know
will try to get a video uploaded of engine revving high etc... and add details as i go

thanks in advance

 

[Daniel_]

I had the same problem last month with my granddads -01 1.4l micra. P0171 system too lean.

Ordered an ebay MAF for 25£, solved the problem. The Bosch ones are prone to failure, the nonames work great!

 

[xeonzerox2]

okay i baught a new noname one and now trying to put it in, looks like previous owner tried also by looks of screw heads haha
although my light engine check light hasnt returned for a while now which is strange but hey im not complaing,
i took these photos to just show what live data is throwing at me. can anyone tell me if anything is odd or not normal, i tried to search for normal readings on the interweb but got very unclear anwsers

maf doesnt change much even when revving
o2 sensors go from about 1.02v down to 0.3 ish quite often

this was after a afair bit of driving but was sat at idle

thanks in advance

 

[frank]

you need to be cruising or holding a fast idle to check the lambda sensors really

 

[Daniel_]

What he said^^

To check Lambda,hold idle over 2000rpm. The quicker it changes between 0V and 1V, the fresher the sensor.

MAF shouldn't need to change much. This is for a SR20, but should be about the same

One thing I found strange from those pictures were T.P.S = 9%? You sure you didn't press on the gaspedal when taking those pics?

 

[xeonzerox2]

yes its was idle with no throttle atall
and will try again tonight after work

 

[SuperMarchFr]

I found !!!

It's a PCV valve !!!