Ok guys just replace 2 a/f sensor 2 hours ago . cel came back with p1153 and p0125 after 3 miles of driving . should i change the last one too the one all the way in the back ?

 

I would pull off the cables and run the test again, if you still get the lights have a mechanic check it with the advanced OBD2 sensor I mentioned so they can get the readings off both banks.

I can tell you it is not unheard of that one bank will show error and even after chaning the one bank, there is still an issue necessitaing both A/F sensors needing to be changed. The reason for this is one is new and the one on the other bank is not (hence the degraded efficiency over time).

I will tell you that should this ever happen to me, I would change both banks given that I race and I don't want silly readings, but for daily driving this is not necessary unless the reading off of a scanner show otherwise.

 

ok changed the other one also now im waiting for cel to come back . i will let you know . thanks again.

 

ok guys im confused now i had just installed three 02 sensors why i still get cel code p0125 and p1150 after just driving 3 miles ?
pls helpppppppppppppppppppppppppppppppppp

 

and also brand new maf sensor .

 

Are they pending or actual mature codes?
Have you reset the ECM? (If you don't have OBD-II scanner, disconnect the battery and hold brake pedal for 30-40 seconds)
3 miles is not enough, drive another day and then reset it.
What is your MPG?

 

mpg before i change sensors 15 mpg today 17.3 mpg anyways i also unpluged batt. cables for 1 hour after that drove it for 20 miles the first 3 miles it came back on again.

 

also the codes says pending.

 

how do you reset ecm?

 

Relax, probably P0125 is mature and P1150 and/or P1130 are pending. They are just new and need a break in period. Reset them after driving for a while.
Here is a quote from another guy:

"The FSM does not state anything about resetting the Main ECU computer, nor have I been able to find out any information indicating that new O2 sensors have a start up or break in period. But, the following experience makes me believe it might take the O2 sensor longer to fire up and operate the first time.

I started my vehicle with the BR-3 scanner attached and watched the new O2 sensor voltage output as the engine warmed up. It seemed that it was taking an abnormal amount of time for the system to go into closed loop and, for the characteristic sine wave swing of the O2 sensor to become evident. So I decided to take the vehicle on a short drive to really heat up the engine and sensor, and with the BR-3 scanner connected. The check engine light came on with a PO125 error indicating that there was insufficient coolant temperature for Closed Loop control.

In essence, (and knowing that all else was in good condition), this error says that the Main ECU was not seeing the O2 sensor characteristic sine wave swing after waiting 140 seconds which, should have been enough time for the signal appear. I kept driving a little further and eventually begin to see the proper O2 voltage swing. I stopped and reset the PO125 error and have had no further problems. So this tells me there may be a longer first time heat up period for the O2 sensor to begin generating the expected signal.

Lastly, my gas mileage has increased back to what the vehicle was originally getting."

Source: Dan Eddleman http://www.4x4wire.com/toyota/4Runner/tech/O2_Sensor/
Hope this helps.

 

ok i will drive it for a while and see what happens. thanks again i ll let you know what will happen next.

 

I had this code before. I replace the Air fuel ratio sensor (by the radiator) with OEM (denso) and no more CEL. You might already now this, that someone replace their A/F ratio sensors with Bosch and the CEL keep on coming back. But when they replace it again with Denso, CEL is out.

 

I Did Use Denso On All Of Them Actualy I Jus T Reset Again So Far I Have Driven 90 Miles It Has Not Came Back On Yet. Thanks Again Meetya And Ryan For Your Time.