Hey guys - complete noobie here. Just wanted to get some expert opinion. I've got a 2003 A4 Quattro and the engine light's been on for a few days. Got my local mechanic to, using the OBD, tell me it's the oxygen sensor. I've been experience a loss in power and acceleration, which I guess, can be attributed to a bad oxygen sensor.

My question is, where can I get one online and more importantly, is there one that you guys recommend? Will any O2 sensor (that's advterised as working for my car) do the job? Are there any ones I should avoid? Anything else I need to know?

You guys are the best!

Thanks.

 

www.ecstuning.com seems to have to have the best prices on B6 02 sensors.

 

Thanks for the reply. What's the difference between that and something I can get on eBay for about $20-$40 or so?Will it still work?For example, http://cgi.ebay.com/ebaymotors/OXYGE...spagenameZWDVWor anything else on it?

Sorry if this seems like a dumb question to most of you guys

 

Stay away from ebay 02 sensors unless its a wholesaler on ebay selling bosch/name brand products. Especially when it comes to somehting like an 02 sensor.

 

Ah, ok. But still, even with the "Bosch" name brand, the prices don't seem to add up: http://cgi.ebay.com/ebaymotors/NEW-B...spagenameZWD1V

The guy has a 99% feedback rating, so it's unlikely he's ripping anyone off. Thanks for the help! I should find out if it's my front or rear O2 sensor that's off.

 

But thats just for the rear 02 sensor, which has nothing to do with performance. You need to be sure wether its a pre or post cat 02 sensor that you need before shopping. They are different.

Oh yeah, you realize that^

 

Ah, if what you say is true (that the rear one doesn't affect performance), then it'd have to be the front one (since I noticed a loss in acceleration/power), the pre-cat O2 sensor. Thanks for your help!!!!

 

FYI - here's one that I found for a really good price. It should work with my 2003 A4 Quattro, right?

http://cgi.ebay.com/ebaymotors/NEW-B...QQcmdZViewItem

 

Yeah that looks like itd work^ But it doesnt have a part #that it replaces, so I dunno. Should work though.
Be absolutely sure that its the front or rear that you need though. If you have the car with you, drive to autozone and get your ecu scanned for the fault code that identifies exactly which 02 sensor is ******* up. You normally dont all of a sudden just lose power/mpg, its a very gradual process over time, they get lazy, so its sort of hard to notice. If you have anywhere near 100k miles on the car, it should be replaced no matter what though.
Im loving the improvement that my new 02 sensor made at 91k. I didnt get bad mpg before, but I averaged 34 mpg on a recent trip, and the low end power is more smooth and torquey. Probably not a big hp/tq increase, but the difference is noticeable.

 

what OBD system did he use? what was the code? only reason im asking is the 2003 car needs to be scanned with CAN bus ( VAG-HEX ) not the old OBD II