P code P0431

[navygm1]

Warm up catalyst efficiency Bank 2 below threshold.
Already replaced both O2 sensors on bank 2. Took a look at the cat with an endoscope and did not see a blockage.
What else could the issue be?


Sent from my iPhone using Jeepz.com mobile app

 

[navygm1]

Also it is a 2006 wrangler.


Sent from my iPad using Jeepz.com mobile app

 

[JPNinPA]

Did you use NTK O2 sensors?

P0431 is Bank 2 sensor 2. That is the last three cylinders before the firewall and the O2 below the cat.
1) If you pull the O2 and it looks flattened on one side your cat is on it's way out. 2) You could have a exhaust leak on that header. Last bolt is known to back out over time. 3) Bad O2 sensor.
Try to reset the CEL to see if it comes back. it may take 4 days to come back.

No blockage was there anything in the cat? Mine was empty.

Easy way to check exhaust leak.
Hook your shop vac hose to the vac output to use as a blower. Then connect the other side of the hose to the exhaust tail pipe. You might duct tape nit on. When engine is off and cold. Turn the vac on blowing up the pipe. Feel around the connections for leaks.
Sent from my iPhone using Jeepz.com mobile app

 

[navygm1]

O2 is new.
I will check the other stuff


Sent from my iPad using Jeepz.com mobile app

 

[navygm1]

The 2nd cat was missing a bolt, so was lose. Replaced bolt, still got P0431. Took O2 sensors out and used an endoscope to look through the upper O2 connection, saw only the honey comb.


Sent from my iPad using Jeepz.com mobile app

 

[JPNinPA]

Is the new O2 NTK brand?
Try the vac exhaust trick to be sure there are no leaks. It doesn’t take much.

Did you clear the codes?


Reset PCM

1.) Disconnect the POSITIVE battery Terminal and touch it to ground for 30 seconds to discharge the PCM capacitors, which maintain the Adaptive Memory.
2.) Reconnect the Battery Cable.
Turn Ignition Switch to the “On” position but DO NOT start the engine.
3.) Turn Headlight On.
4.) Turn Headlights Off.


Sent from my iPhone using Jeepz.com mobile app

 

[navygm1]

Is the new O2 NTK brand?

•Try the vac exhaust trick to be sure there are no leaks. It doesn’t take much.

I used the shop vac to blow through the exhaust. Cat 1 was leaking, tightened that up. Took the O2 sensor out of cat bank 2/1 while the vac was blowing got a great flow of air. While I had the O2 sensor out I switched nozzle to suction and got great suction through the hole. Put everything back together.


Reset PCM

1.) Disconnect the POSITIVE battery Terminal and touch it to ground for 30 seconds to discharge the PCM capacitors, which maintain the Adaptive Memory.

•Took the positive side off and the connector fell apart in my hand. Grounded it out.

2.) Reconnect the Battery Cable.
Turn Ignition Switch to the “On” position but DO NOT start the engine.

• did.

3.) Turn Headlight On.
4.) Turn Headlights Off.
• did

Sent from my iPhone using Jeepz.com mobile app

Now I just got to drive for a bit to see what happens.



Sent from my iPhone using Jeepz.com mobile app

 

[JPNinPA]

Got my fingers crossed.


Regards,
JPNinPA

Sent using TapTalk

 

[navygm1]

I think i found out what the problem might be! SB 25-005-13

 

[JPNinPA]

I take it you still have the code. Thanks for sharing that TSB. Never saw that before.

Best part is the last line

NOTE: Vehicles included in this Service Bulletin have a lifetime coverage warranty for this repair. See Warranty Bulletins; U.S. D-13-38, Canada SAB-2013-29 or International ID-13-12 for details associated with the extended warranty


Sent from my iPhone using Jeepz.com mobile app