It has been like a year or so that I was told I need 02's. I think they said there were 4 of them. Can they tell if it's just one or 2? the guy at the store was pretty useless....is there a way I can pull codes myself?

 

louvit, you have 4 O2 sensors in your car. You have 2 upstream sensors and you have 2 downstream sensors. These sensors are different, so, please keep this in mind. You can think of them this way (and some places also refer to them this way) in that the upstream sensors are "fuel trim" sensors and the downstream sensors are true "O2 sensors". They both work on very similar principles, but to the computer, they do completely different jobs.

As for pulling the codes yourself, there are a few options for you. If you don't need a reader yourself, a lot of autoparts store will let you borrow one from their "tool rental" area and then you can go out into the parking lot and read the codes yourself (plug in reader, turn the car to RUN, press "READ"). If you want your own reader to have so you don't run to the store when you want the codes read, you can get a basic handheld reader (like what you will get at the auto parts store) for around $50. Please keep in mind that all you are going to get is the codes and that is it with the basic reader. The more you spend, the more you are going to get. The cheapies will only give you the 5 character code, the slightly better ones will give you a short description, the more expensive ones will actually read values from the computer and tell you certain engine parameters. How much of a reader you get is up to you.

The last reader you can get is called an "ELM 327". These are normally bluetooth and you use your Android based phone to interact with the car. Sorry, if you have an iPhone, there is no app that I am aware of to make this unit work. Once you have the Elm unit, you can download a free app (called Torque) and then you can see all the codes, get all the real time data, etc. You get all the options of a $300 reader for somewhere between $20 and $40. The thing you need to be aware of is there are 2 different style readers out there. You have the one for the older cars (before the wiring change in early 2004) and then for the newer ones (after the wiring change). So, make sure you get the correct one. The older cars have the cheaper reader.

If you need help in replacing the sensors, let me know. It isn't too bad. The big problem is just getting a correct wrench in the area to get to the sensors. If you have bear claws like I do, it is easier said than done.