My neighbor recently bought an 2001 Camry. He took it in as the CEL came up and his mechanic told him it was a faulty O2 sensor, and that he would replace the one in front as he claimed they fail more often. He claimed he could not determine which O2 sensor it was based of the code (OBDII). As he was driving home the CEL came back on. He returned to the mechanic who replaced the other O2 sensor in the back. This is a V6 so there is also a 3rd sensor after the cats, which has not yet been replaced. The mechanic also claimed generic sensors would not work and he needed the $300 Toyota genuine part.

My questions are these:
1. Am I right in that the only reason the front O2 sensor "fails" first because its easier for the mechanic to get to?
2. Is it bullshit that the mechanic can't determine the specific sensor from the OBDII?
3. Is it also bullshit that generic sensors do something "different" and cannot be used on Toyotas?
4. $300 for an O2 sensor seems high, all the dealerships are closed today but online they seem to be about half that. Is that what they really go for?

He says he trusts this mechanic and he's been going to him for a while. He nods towards his Tahoe and says the guy did the work on that. The Tahoe was taken in for a transmission failure and left with a new transmission, transfer case, and engine.

Mike

 

1. Not sure, never seen the underside of a Camry, I don't know where the 02's are located.

2. If he was any kind of quality mechanic he would have the proper diagnostic code scanner for an OBDII car, which would tell him exactly which sensor is not metering properly.

3. I'm sure there are other OEM type replacements available. He probably mentioned that because Toyota genuine parts are much more expensive than a Bosch replacement, for example.

4. $300.00 does seem very steep for ONE oxygen sensor, but for a Toyota genuine sensor, you never know.

 

His best bet is to take it to a local carquest or pepboys and have them scan the code for him. They will tell him exactly what is going on.

 

02 sensors aren't cheap

 

1. That should be a non-issue, location seldom has anything to do with why one sensor fails over another. With that said some people are just lazy.

2. It is BS even the most basic code scanner will throW a code Pxxxx, then if you have a cheap scanner you look the code up(If you have a middle of the road scanner or better it will tell you with out manually looking it up) and it will tell you that you had an 02 sensor problem(be it slow response, no activity, heater circuit high/low, etc) and then it will say bank 1 or 2(unless your working on a veyron) followed by sensor 1 or 2(1 being upstream, 2 being down stream). The only problem is 02 sensors can trigger one to go after another. For example if the down stream sensor is saying its lean by fault it will make the car run a bit rich and can damage the upstream sensor and only after the downstream sensor is replaced it will lean the car out a bit and then cause the upstream sensor(s) to fail. Even though the initial diagnosis should be easy, one faulty sensor may cause another.

3. It is BS, while I wouldn't search for the cheapest sensor a universal Bosch will work in just about any car(they come with a great set of directions to make sure you retain factory plugs and splice them properly in place). With that said, its often cheaper to get a direct fit when you factor in labor to make the universal fit. Of course if your a home mechanic your labor isn't terribly expensive.

4. Some 02 sensors are stupid expensive, but shop around and make sure your not being taken advantage of.