Engine light =p071b bank one lean

[jls1mod]

can any buddy help me with this one? Vehical drives like it isnt getting enough gas but the fuel pressure is good.

[truckpoor]

I'm guessing the code is P0171, system too lean, (bank 1).

Mine turned out to be the mass air flow sensor. There's a whole list to check, so if you want me to, I'll go grab my repair manual and check it out. I've got a 2000 Tacoma V6. I'll need the info for your truck, 4 or 6 cylinder.

[chester9ll]

i have a 2000 tacoma with a 3.4l v6 5-speed and i am having the same problem. ive changed the o2 sensor before the cat and the check eng light went out, but my truck seems to be running worse. i checked the mass air and it was within limits. i dont really know what else to do other than change the injectors but i want to save that till nothing else works. im going to change my plugs since the truck was running lean it may of fried a plug or 2. if anyone has any suggestions i would appreciate it.

[Brian R.]

For P0171 code (easiest and cheapest first)

1. Check your air induction system for leaks or broken hoses/connections.

2. Put some injector cleaner into a tank of gasoline and see if that helps after you've gone through a tank of treated gas.

3. Buy some no-residue sensor or electronic contact cleaner (NAPA or elsewhere). Remove the connector from the MAF meter spray both sides of the connector thoroughly. Spray the cleaner into every possible exposed portion of the MAF meter in the intake tube and let the cleaner evaporate. Reconnect the MAF meter.

4. Test the engine coolant temperature sensor - replace if out of spec.

5. Check your fuel pressure.

6. Replace the HO2/A-F ratio sensor with the correct sensor (Bank 1 Sensor 1) - Get a part number from a Toyota parts department with your VIN.

7. Replace the MAF meter.

Somewhere along this process, the light should go out and stay out. Most commonly, it is cleaning the MAF meter and connector that solves the problem.

[Brian R.]

Originally Posted by chester9ll

i have a 2000 tacoma with a 3.4l v6 5-speed and i am having the same problem. ive changed the o2 sensor before the cat and the check eng light went out, but my truck seems to be running worse.

Check to make sure you have the right sensor by getting a part number from Toyota parts department. Give them your VIN for reference. Some vehicles have HO2 sensors and some have Air/Fuel Ratio sensors. Put the wrong one in and your truck will act like you said.

http://www.autoshop101.com/forms/h37.pdf