Quote:
Originally Posted by KaToFLR
Damn my CEL came back on. 
Freaking same codes as before - Po171 Bank 1 and Po174 Bank 2
Dont know if it the o2 sensors, the MAF or fuel injectors? I ran some fuel injection cleaner, could not find any leaks and cleaned MAF.
What should I do? 
Do I start with the MAF then the o2 sensors.......... |
Since both are reading too lean I would expect it to be something that relates to both, like the MAF. They both came on at the same time it is unlikely that both failed at the same time. Unless it was your very first time driving at highway speeds after you bought the car.
To test the MAF get on the highway at about 50 MPH. Floor it and if the engine revs up (~4,000 RPM) but there is no power and/or it doesn't shift then it is probably the MAF. If it pulls fine then your MAF is probably okay.
Caveat - from what I have read MAFs fail in a myriad of ways and what I described above is just how mine failed and how I determined it failed. You can also just check the voltage at various RPMs, but that is a little more intrusive.