Hoping someone could help me track this down before I have to break the bank. I drive a 2000 3.4l v6 with 50K and about a month ago my check engine light came on and gave me a P0171 system too lean bank 1 code. I checked everything out and just thought that maybe the sensor tripped for some reason reset the code and went on my way. The light came back on with the same code so I pulled off the intake, cleaned the MAF, put a little silicone around the lip of the intake before fastening it back on, and checked as best I could for leaks by spraying carb cleaner. I felt a huge difference in my truck, the MAF was pretty dirty on one side, but now the light came on within a few days instad of weeks and it's still that damn 0171. I was thinking it is time for a major tune-up since my truck has been stretched beyond the regular maintenance. Or that my injectors may be clogged, or sensor replaced. Any thoughts?

 

Your 2000 should fall under the 5yr/60K powertrain warranty. I would take it in to the dealer.

 

Thanks for the help, but the bank 1 sensor is 3/36k and I miss it by two months.

 

If you have a CEL, the dealer should diagnose it for free while in the warranty period. That CEL may be related to a powertrain problem, or an emissions problem (which is covered for 10/100K).

I would avoid telling them about the MAF cleaning and silicone sealant you did. That would just give them ammo.