cbw6852

I was just wondering how vital the O2 sensors are to the car. Are they absolutely necessary for the car to run well? Thanks

boschmann

The engine management system uses the O2 sensor informantion to control the air/fuel mixture. Aside from being illegal to remove, the car will not run properly & engine damage can occur if they are removed. That said, if you do a Google or even eBay search you can find O2 sensor simulators that are used to defeat the problems created by removing the sensors. They are an electronic device that simulates properly working oxygen sensors. They are usually used by people who have put on performance items altering the engine's mixture and/or performance exhaust systems eliminating the catylitic converter. Officially they are not for road use. I would advise if you are doing this to have it done by knowledgabe people as again damage can be caused by improper installation.

cbw6852

Bosch thanks for the reply. I was asking becasue i was told that i needed to change my O2 sensors. What is the normal price to change the O2 sensors. I was researching them on the internet and I found two kinds, on one it said "Behind Catalyst" and the other said "Before Catalytic". Do i need to replace both of these. And any other information about replacing the O2 sensors, like where a good place to buy them is would be great. Thanks

boschmann

Are you changing due to a code being set or just as a maintenance precaution? You don't have to replace in pairs. In my experience I've seen the forward (pre-cat) sensor fail most often, but depending on the mileage (>90K) I will sometimes replace both. Be careful if you're replacing due to a check engine code other than the P0130-PO140 type codes. I've seen MAF's set lean/rich limit codes mistaken for O2 sensor problems. As far as price, the best price I now get is through VW. My cost for certain sensors has dropped as low as $16, an unbeatable price since universal Bosch 4-wire sensors from parts stores run $90. VW is evidentally trying to prevent outcry for a recall due to high failure rate.

cbw6852

Thanks again. But i am not smart when it comes to cars. Could you clarify what a "P0130-PO140 type codes" is. Also what is an MAF. I was asking about the O2 sensors becasue my mechanic said they were bad, but the car does not feel like it has any problems and it performes like it did before the light went on. And do you get the sensors through vw.com. Thanks.

boschmann

What I was asking is why have you have centered on the O2 sensors. Who told you they needed replacing & why? Those codes I mentioned are typical O2 codes, other codes can be set implicating O2 sensors while actually being something else, e.g. lean/rich limit codes actually being caused by the MAF. MAF = Mass Air Flow sensor, a very common part to fail. I will often buy such parts from the local VW dealer, as I find I can get very good prices on certain parts such as certain O2 sensors. That $16 price was for the more common 2.0 sensor (haven't priced a VR6 lately). By the way, I am assuming you have a VR6.

abutle1

I am curious about the same thing. I just got a quote from a shop to replace my oxygen sensors on a 4cy Passat for $175.91 and $107.36 - seems like they are gauging me. Also they said 1 1/2 labor- Does that seem right?

boschmann

It depends on if they are using VW parts or not & where you live. For here in the Southeast it's a bit high.

abutle1

Thanks for your help this thread has really been informative!