Another CEL 171 problem! - Toyota Nation Forum : Toyota Car and Truck Forums

Tony-bobs · 08-21-2009, 07:17 PM

I got the code 171:running lean bank two. I read on here that it is usually fixed by cleaning the MAP sensor, so I tried to do that today. Problem is that I can't get the stupid thing off. I tried a screwdriver but soon realized that it was a star wrench, it was pretty dirty in there. So I bought a set of star wrenches, but none of them fit. Am I using the wrong tool, or am I just dumb? Also I noticed this thing hanging down off the back side of my engine so I took some pictures:
http://i60.photobucket.com/albums/h1...6/IMG_1766.jpg

http://i60.photobucket.com/albums/h1...6/IMG_1771.jpg

http://i60.photobucket.com/albums/h1...6/IMG_1768.jpg

http://i60.photobucket.com/albums/h1...6/IMG_1767.jpg

Should I be worried that it isn't attached to anything on one side and its hanging by a tiny wire?

tech8 · 08-23-2009, 07:58 PM

P0171 is usually the Mass Air Flow (MAF) sensor being dirty, not the MAP sensor.

This other thread shows the location:

mass air flow sensor location

Tony-bobs · 08-24-2009, 01:42 PM

Sorry I meant the Mass air flow, wasn't paying attention. Do you have any idea what the hanging thing is?

huangxin · 08-24-2009, 05:33 PM

the MAF sensor in my car is held on by 2 "+" screws.

i think that's a ground wire or something. it supposed to be screwed onto the valve cover.

there are two 10 mm nuts holding the plastic strip covering the wires that connects to your coil packs. the thing you are holding should be placed under the nut on the driver's side right above the oil cap if you look from the front of the car. take the 2 nuts off, lift up the black plastic strip, put the metal part of the "thing" onto the screw, then install everything back.

i don't really know what it's there for either, all i know is where it goes lol. since it only got one wire, i think it's a ground.