02FormulaKCMO

My '02 Formula w/ only 36K has this warning light on (since last night).

a) I use 91 octane so it shouldn't be fuel.

b) I don't have a K&N or any oiled air filter.

c) No mods to the exhaust except a flowmaster with 3.5" tips, that have been on for 5 months.

Something related to emissions standards????

Any idea of the cost to get it checked out and turned off????

THANKS for any help!

phantomzer0

iTrader: (17)

it could come on for any number fo things really. i would take it to autozone or something and have them scan it. autozone has this service for free.

RPM WS6

iTrader: (3)

That light could be anything. There are tons of Type A and Type B (the two types of codes that will illuminate the MIL) DTCs for an OBDII car.

Best bet will be to get the car scanned and let us know the findings. From what I hear, Autozone will scan cars for free just to give you the code. Or find someone local with a scanner.

joshp14

iTrader: (5)

Wouldnt be surprised if they found a P0420.....

davered00ss

iTrader: (4)

Auto Zone scan's codes for free. If you don't have one locally, post up in your local forum someone will have a code scanner to scan it for you. We can't help you if we do not know the code.

davered00ss

iTrader: (4)

Probably bad rear O2's.

02FormulaKCMO

Good call.......it was a bad O2 sensor in the rear.

$67 to replace at Autozone.

Since there are 4 of them, can I expect to see this again??

Thanks.

staringback05

iTrader: (8)

the rears arent that big of a deal, they dont really do much like the front ones do....i just got a new motor and i blew the rears out car still runs fine...just dont let the fronts go out

02FormulaKCMO

hypothetically......what would happen if i kept driving without fixing this rear o2 sensor right away?

2001NBMZ28

What was the code? Rear 02's monitor the cat status - sometimes they'll (AZ) will tell you its an 02, gets replaced and doesn't fix the problem. Plus the code will tell you which side it is. Generally it's OK to drive for a while with SES on as long as it doesn't start flashing or you notice a decrease in performance, like if the cat is clogged. If it's P0420 or P0430 stock cats are covered under the federal emissions warranty up to 80K.

02FormulaKCMO

The code was "P0155 - Bank 2 Sensor 1"

Driver's side rear (after catalyst)?

Do I need to replace both rear o2 sensors at the same time - although only one is bad?

Bosch is $65..........another brand calld SNG is $48.

Does the brand matter?

Thanks.

2001NBMZ28

They did tell you wrong if they said rear. P0155 is the passenger side PRECAT 02 sensor, not a rear.

Edit: Bank 1 is driver side, Bank 2 passenger side, Sensor 1 is precat and Sensor 2 is postcat for 02s. I'd change it as soon as you can, don't let it go.

02FormulaKCMO

I will double check..........thanks.

#1T/A

iTrader: (1)

Otherwise if you go do the work yourself its real simple, just raise the car at any place where you can rent a lift, then take out the old sensor and replace it. I did this yesterday and I am NO mechanic. Just take it easy and don't stress.
Also, I'd recomend buying a cheap scanner tool. Most of these go for less than 50$ and can save you much money. I.e, had I turned my car in to a shop to do the same work, it surely would have cost way over 300$ to change O2s (sweden). yesterday I payed a total of 3$ (!!!!) in expenses to change the o2. It feels goood

02FormulaKCMO

Last O2 sensor question:

Do I need to spend the $65 on Bosch or can I go with a cheaper universal sensor like SNG or Denso?

Autozone said that all 4 sensors are the same (Bosch # 13444).

Dealer said they aren't.

Just for laughs I calld the dealer for a quote:

Dealer wants $250 installed for one sensor!.....Ha-Ha

02FormulaKCMO

Wouldn't you know it.......the "SES" light has gone back off now.

I guess my o2 sensor is ok again????