Endless upgrade cycle?

Hello everyone, my wife has a 2002 2.4L 2WD KingCab Tacoma and the check engine light came up. First I checked the engine code that said it was the fuel/air sensor. So I installed a new fuel/air sensor between engine and catalyc converter, but the light didn't disappear. I thought it was because I had bought a cheaper aftermarket sensor so I installed the Toyota, Denso sensor, now I have engine code p0171 saying my Bank 1 is too lean. ASE certified Master Technicians say the most likely solution is a new MAF sensor. The truck has 205k miles.

My question is, will this indeed be my solution, or will I get another error code after this? Can it be the Engine Computer Unit? Does anyone here have experience with this aftermarket Denso sensor: https://www.ebay.com/itm/DENSO-Mass...e:2.4L+2438CC+l4+GAS+DOHC+Naturally+Aspirated ?

Regards,
Bas

 

What was your original code? P0420? If that's the case, the other possibility is the catalytic converter. For trucks of a "certain advanced age" it isn't uncommon for the cat to start going bad.

There's MAF sensor cleaner you can get. Might as well do that, along with cleaning your throttle body, too. If that's never been done before, that should be done anyway.

 

Af codes don't mean you need a new sensor. They mean that's the sensor that's showing an error. So something upstream that causing a lean condition will show an error downstream .

 

Id be hesitant to order Denso stuff off ebay that's priced that low. A lot of scumbags like to make/sell counterfeit Denso auto parts and distribute them over ebay/Amazon.

 

Apparently there is no government body controlling the quality of aftermarket parts...like the FDA with food. Thx for the answers!