PO141, PO156, PO132 &PO161 for 1999 V6 E320 with 167500 KM, but car driving smooth. fuel economy is 10 liters per 100kms.
Advise would be greatly appreciated...

Thanks.

 

I have 1998 E320 with the same problem. Had it for years. You have to understand that this is an oxygen sensor preheat fault indication. It is valid only during engine warm-up. If the check engine light comes while driving, it's a computer glitch you can ignore. If it does not come again for 200 miles, the computer will clear itself and the check engine light will go out. You can do the same with an engine code reader and clear the fault with it. I have been doing this and the check engine light some times will not come on again for a montyh or two.