Thread: Check engine light on

So over summer my car threw a code saying the bank 1 o2 sensor was bad. mileage was bout 10mpg. found out it was the one after the cat. changed it and everything was going smooth, mpg went normal. recently it threw the same code again and my milage didnt really get bad but not as good as it was. had it scanned said the same thing again. changed it last week, had the code erased, stayed off for a week with good milage. today light came on and i took it to autozone and it threw the same code again twice, said "bank 1 oxygen sensor below threshhold". would that be the o2 in the u-bend? this is the 3rd o2 sensor im on and dont wana drop $$ to have it happen again. heard a clogged cat could be eating the sensors. is there anyone who knows what o2 i need to change or how to unclog a cat beside buying a new dp?

no my car is stock minus a CAI.

mkkk. im bout to go try that because my cars already kinda warm

ok so i just drove my car for bout 20 mins (it was already warm). headers werent glowing and neither was the dp/cat. i think its plugged but not bad becuase sometimes my car chugs along but not always. how hard is it to get your dp out?

mkkk ill try this tommorow and hopefully itll help. so just take a bar and like jam it through and wiggle it around? no special techniques lol?

dude seriously use freeze off. It's better than wd 40, pb blaster, and liquid wrench

sensor 1 bank 2 is the sensor in the uben behind the cat. sensor1 bank 1 is the one on the downpipe behind the rear manifold.

it didnt say sensor 1 or 2. just "below the threshhold". not sure if anyones seen that before.

on my list of obd2 codes there isnt one that states heated o2 sensor - below the threshold. what was the code that popped?

p0141 i believe.

p0141 is your rear sensor, bank1 sensor 2. its the one in the ubend rigt behind the cant. i would check the fuse for the o2 to make sure its ok, should be a 10amp red fuse. then get under the car visually inspect the wiring harness around the sensor make sure nothing is showing or warn out. make sure the plug is set in all the way that code usually doesnt come up because of a clogged cat. its either a faulty sensor or a short in the system or bad fuse as i stated.

im gona have to check the fuse. the o2 is literally not even a week old. and the one before it was like 5months old. which box is it in, under the hood or in the glove box?

um id like to say in the hood. if not id just check the one in the glove box to lol

mk thanks. ill update ya guys tommorow

yea let us know and if i think of anything else ill let you know. oh and fyi just to let you know that rear sensor from auto zone is about 78dollars. and if you do end up replacing it again rent the o2 sensor wrench makes life easy

yeh this ones from autozone. last one was from murrays i think. ive mastered gettin em on and off with a regular wrench sadly

hey joe whats that fuse called? me and my dad looked in the manual and on the boxes and no "o2 fuse"