looking for back yard mechanic to work on 2001 corolla P0171 lean on bank 1
 

I am not sure where to start

well I start cleanning the maf sensor using brake cleaner. but no effect. in fact the maf sensor looks pretty clean.


these were done on the last maintenance
310 k - 312 k , the car has 314000 kms at the moment
oil
coolant
thermostat
water pump
plugs
air filter



All I got from reading the google
look for vacuum leak
o2 sensor may be dying?


any backyard mechanic in burnaby new west area looking for work??

Replace the maf sensor.

i agree... and this is coming from two toyota professionals...

Check all your vacuum lines for leaks, try to spray some intake medic around your intake manifold and see if it makes a difference. If your scanner lets you see the short term and long term fuel mixtures check those out, should be between -10% to about +10%, max -15% to +15%. If those are good and within spec then it is your maf that is causing the issue. If they are not within spec it means you have a intake leak or too much fuel, most likely a intake leak. if it says +10 or +15% etc, it means it is trying to add fuel to compensate for the unmetered air after the mass airflow sensor hence a intake leak.

yee replace that maf sensor i worked on a 03 corolla and if u hook up the scanner n read the maf the readings will be off but it isnt enough to trigger a check engine light

my obd reader is Scangauge 2 so I can't check the fuel mixture.

I wonder if anyone here will let me borrow their MAF sensor to see if the problem go away? :) I know the code comes back 10-30 mins after I clear it

I don't want to spend $200 on maf sensor and finds out it vacumm leak or other sensor?
what do you guys think ?

MAF sensor.

if u dont want to replace the sensor take it to a shop n hav them diagnose it and then u hav a for sure answer