baudenfj

I have a A6 quattro - 1998 2.8 liter AHA engine..

I replaced all four O2 sensors! I know I do not have a leak in the exhaust! The car runs great, does not smell and get great fuel economy.

I have a CEL and the error code

16816 - Main Catalyst Bank2: Efficiency Below Threshold PO432-3500

How can I get rid of the error code to pass emissions! I was thinking buying an aftermarket cat and having it weld in!

Is there an easier solution!

Help appreciated.. Cheers,,,

01 2.7t

try doing a complete seafoam treatment it worked the last time i needed to clean out my cats

4Driver4

Bang on the cat to see if it's full of pieces. If so, replace with bolt in cat from Connecticut Cat; if not just reset the light and wait for warmer weather.

If you need to pass emissions, reset the light then force readiness (VAG-COM) on all systems except cats. That should set enough readiness codes to pass.

baudenfj

Thanks! Do I need the full version of VAG-COM to reset the readiness codes? Is the emissions testing center able to tell weather the CEL and the readiness codes have been reset?

Cheers...

4Driver4

Full version required.
They might assume that the CEL was reset if all readiness codes are not set, but that shouldn't matter them. Either the car is in compliance with "pass" requirements or it fails. They should not care about anything else.

When you reset the CEL, it clears all eight readiness codes. As the car is driven, the ECU checks the health of all systems and gradually records readiness. Most states will pass you with 6 of 8 codes complete. The key is getting the 6 or 7 that will pass readiness to complete before the 1 or 2 codes that fail. Use the full version of VAG-COM to set as many readiness codes as possible while avoiding the ones that fail.

baudenfj

Thanks.... BUT...

Is there a way to trick the ECU and install a resitor in series with the post cat oxygen sensor to get into the "green"? This would be the most elegant solution to get past the emissions test.

Cheers,...