Baloo588

SO my 2012 Audi A8L with 141k miles has check engine light and some misfiring cylinder codes on the scanner. My dealership says its a pre-cat O2 sensor that needs replacement and will cost a staggering 961 dollars!! IS it really that much because the parts themselves are that expensive? Any insights into this and how much it should cost reasonably? My dealer is very good and will see if they can get some extra help from Audi for this.

MP4.2+6.0

You can get your typical Bosch OES heated sensor in the $75 to $100 range from Amazon, using even my ultra low volume D3 W12 as a benchmark. To be clear, I mean the full plug compatible one--correct cable length, end connector, correct color to end connector, etc.--and not the one size fits all splice in ones. Dealer price for the identical sensor, discounted online, was more like low $200's IIRC.

On a 4.2, they are painful to reach--at least from my 2000 A6 4.2 experience with then simpler cats, as well as what people say on the D3 board about 4.2's. But, even with a dealer sensor priced full retail at like $250, that's a lot of pain applied your wallet. If you have a trusted indy, I would try to get the OES sensor (most likely Bosch) from non-Audi channels and have them do the work at a better labor rate.

Twglasgow

Yep, try to go independent. Your situation reminds me of my 90, the cat converter replacement was picked up audi thanks to my service rep. It was $1500 and I don't think the service manager was too happy with the rep. Next one I went to an independent for $300 to $400 bucks. The independents labor rate was not.a lot different but they know you're there because of price.

rally

Yup. Just checked today for the FSI 4.2 the OEM 02 sensors are $75 on Amazon and $212 from Audi. One of the precast sensors is open and easy to reach from the top back of the engine. Didn’t sight the second one from the top.