[Hamilton]

2006 Tundra, V8, 300k+ miles

CEL came on the other day and the code reader showed three codes.

1 - P0171 System too lean (Bank 1)
2 - P0171 (pd) System too lean (Bank 1)
3 - P2195 (pd) undefined code.

Did a bunch of searching here and found a couple of possible causes.

I cleaned the MAF and the codes came back. My next target is the upstream O2 sensor on bank 1 (Driver), I ordered a Denso 234-9051 from Amazon but it says "Right-Bank" is there a different sensor for the left bank? Denso's website doesn't say anything about right or left.

The sensor won't be in until next Friday, is it safe to drive the truck until then? Makes me nervous to drive with the CEL light on...

Also, does anyone know why it shows the P0171 code twice? And what does the (pd) mean on code 2 & 3?

Thanks,

- Hamilton

 

[Professional Hand Model]

You’ll be alright driving around will the check engine light. The computer will just adjust to base line fuel levels. I drove around for about a year with a bad o2 Sensor. These are the ones I ordered and put back in for my 2002 4.7 4wd. The Rear o2’s require different length wires. The 2wd works on the 4wd but not visa versa. Replace all 4 at one time if you can. The rear o2’s need new nuts and those can be had from the local stealer for $8-9. Report back!

 

[Hamilton]

Thanks PHM, Amazon is now saying it will be delivered today, hopefully I can get the old one out and the new one in... Then fingers crossed that is the issue...

 

[LFER]

Hey, similar happened to me a while ago but not with my truck, and, after a lot of troubleshooting, O2 sensor replacements and MAF cleaning, the issue resulted being a clogged or faulty injector. Replaced it and everything went away. Not sure if the same will apply to you but worth checking.

 

[Hamilton]

Thanks LFER,

How did you determine the injector was bad?

 

[tariqansari]

Don't forget to reset the vehicle computer after replacing the O2 sensors. You can do that by disconnecting the Negative terminal of the battery for about 10 minutes.