P0161 Code Won't Go Away

Boboddy

Member
Original poster
Supporting Member
Joined
Dec 4, 2019
Messages
82
Location
Williamsburg, VA
Had a P0161 code pop up for my 01 Sahara. Replaced all the 02 sensors with NTK but it still wouldn’t go away. Went away on its own and came back.

Any ideas? The wiring on the 02 sensor itself is fine but the wiring of the harness for bank 2 sensor 2 is difficult to get at
 
How's it driving? Gas mileage? Speedo accurate?

Any way to monitor live ODB data? I like to watch the voltages and make sure they stay below .9v.

-Mac
 
How's it driving? Gas mileage? Speedo accurate?

Any way to monitor live ODB data? I like to watch the voltages and make sure they stay below .9v.

-Mac

I think it is a couple mph off too and has the right speedo gear. Not sure if it’s related but it struggles on steep mountain roads. Won’t go over 2.5k-3k rpm.

Think that’s the pcm?
 
I'm thinking plugged cat or bad O2s. Or cracked exhaust manifold.

You can remove the O2s and create an exhaust leak (you'll get codes, ignore them) and see if it drives better.

That would point towards plugged cats.

You can monitor live ODB data and watch the voltages on the O2s. Crudely and simply put you don't want the voltage to go over .9v and you want it going up and down with throttle.

And you can visually check your exhaust with a can of seafoam. Start the engine, unplug the brake booster vacuum line from the master cylinder...dip in the bottle...rev it up some and pull it out of the bottle so it doesn't die. Should make a lot of smoke...so this is where a few friends or a couple of GoPros help you spot white smoke coming out of places it shouldn't be...like exhaust manifolds.

-Mac
 
  • Like
Reactions: Offline246
When you replace them, the connector should make a solid click sound which tells you that it's fully connected. They are a pain to access, but luckily you only need to replace them every 75-100K.

You could also try a PCM reset. I do a reset when replacing any FI sensor to force it to relearn and it also helped a stubborn code to disappear.

https://wranglertjforum.com/threads/any-benefit-to-resetting-pcm.15762/post-254238
 
Really take a close look where the wiring runs from that since you’re behind the block above the bell housing

I’m dealing with some things right now and from here on I will always really be paying attention to my harnesses better
 
I'm thinking plugged cat or bad O2s. Or cracked exhaust manifold.

You can remove the O2s and create an exhaust leak (you'll get codes, ignore them) and see if it drives better.

That would point towards plugged cats.

You can monitor live ODB data and watch the voltages on the O2s. Crudely and simply put you don't want the voltage to go over .9v and you want it going up and down with throttle.

And you can visually check your exhaust with a can of seafoam. Start the engine, unplug the brake booster vacuum line from the master cylinder...dip in the bottle...rev it up some and pull it out of the bottle so it doesn't die. Should make a lot of smoke...so this is where a few friends or a couple of GoPros help you spot white smoke coming out of places it shouldn't be...like exhaust manifolds.

-Mac

agree with the plugged cat - that has been seen here on the forum many times.
 
  • Like
Reactions: macleanflood