Tan327

iTrader: (15)

I took my car to the shop and hooked a scanner up to find the voltage of the O2 sensors after reading on here that they should read between 150-900mV ..well bank 1 sensor would read between 40-850 and jumped around like crazy, literally 1 sec it would be at 40 and the next it would be at 800. I'm guessing this means it needs replaced? The others(most importantly bank 2) would stay right around mid 400's. I say others because it showed 2 more, but I assumed the rear o2's were tuned out, guess not.

So am I safe just replacing bank 1 sensor. Anyone recommend a certain brand?

senicalj4579

iTrader: (41)

I would say "around" 0-1000 mv is normal. I think your o2s are fine. Are you getting any codes?

Do you have any rear o2s in place? If not then that explains why they are not oscillating and they are staying around 450mv. Also I think if you have them tuned out then they will read flatlined also but not 100 percent on that.

I have seen my o2s go from "about" 0-1000mv and especialy in the cold they will be slower.
I would talk to a good tuner if you think theres a problem.

Tan327

iTrader: (15)

Thanks, I assumed the one dropping low was bad but a friend of mine on here told me the one that is staying around 450 and not fluctuating much was probably the bad one ..makes sense. And yes I did get code saying both on bank 1 were bad, but someone on here said it could be due to a dirty MAF ..after cleaning the MAF I haven't had the codes come back but I have not driven the car more than 15-20 miles since doing so. I think an over oiled K&N(previous owner) caused the dirty MAF, I chunked it and went with a paper Fram.