TRMNATD

99 ML320, 200k mi.

Have 2 codes show up the other day. I cleared them and as soon as it goes into closed loop it throws the codes. P0141 and P0161.

Anybody have any ideas. I find it hard to believe that both rear O2 sensors would go bad at the same time. I looked under the truck, wires look good (looks like original sensors).

Also checked the fuse at #19 was good, and ground near brake booster is tight.

Thanks for any help

art_arev

Your car is 15 years old. It is very much possible that your post CAT sensors are cooked. Maybe you had 1 bad sensor & didn't know about it & the second one has gone bad as well. Is there a problem with the car or you just did a routine scan?

TRMNATD

I replaced both sensors, and so far so good. I used the search and many people did that, and still got the same codes.

Drove 100 miles today and no cel.

Thanks for the help!!