Based on a recent CEL a Vag-Com report shows it is time to replace the 02 sensors on my C5 A6 3.0…

I'm seeing Bosch brand at about 130-150$, also seeing a generic brand at 40$.

Let's say I grab the cheap ones, common conceptions would indicate a shorter lifespan poor quality on the inexpensive generic brand, right?

Should I go Bosch or save some hard earned cash and go with the generic brand?

 

Go with Bosch.

I tried going cheaper with Ebay ones and I kept getting a CEL and mileage sucked. I eventually pulled the trigger on Bosch ones (sparkplugs.com; autohausaz.com; rockauto.com) and no more CEL and mileage is great!

 

GULP.... I think you are right on this. Thanks!

 

$ 83.17 at Arizona Autohaus (three wires; direct fit)- free shipping after $ 50.
I replaced both of mine and the car purrs like a snug and cozy kitten - no MILs whatsoever.

 

I second on the Bosch.

 

Now the big question... Replace all four sensors or determine which have failed based on the info below?

16805 - Warm Up Catalyst: Bank 1: Efficiency Below Threshold
P0421 - 001 - Upper Limit Exceeded
16815 - Warm Up Catalyst: Bank 2: Efficiency Below Threshold
P0431 - 001 - Upper Limit Exceeded

I am willing to admit that I may need to replace the cats also as indicated above. Visual inspection looked okay no holes or corrosion found.

Just looking to make the A6 purr instead of chugging gas like German ale... hah

 

I would replace first only the 2 upstream ones (before the cats).

 

If the cats from a 95-98 fit (same design) a C5 then you can get new ones for cheap off MacAutoPartsdiscounts - Ebay. If the cats are bad, then spending money on O2 sensors would be a waste.

 

+1 on replacing the pre-cat O2's only.

the post-cat O2's really have no function (that you can notice anyway) and are wasted dineros.

 

thanks all.. I had the same question.. I'm going out to look where my front O2's live.. easy to get to? and plug the new ones in? thanks Dwight in New Orleans