2015 Cherokee stumbling

[tworley]

2015 Cherokee Latitude. 2.4. 109k miles. Plugs changed at 95k with NGK.

My wife's jeep. I've yet to experience it but she says it stumbles at idle (RPM dipping below 500). I plugged in my obii dongle and Torque app. One thing I noticed right away was the O2 sensors are a bit sporadic. These are at idle only.

Bank 1 Sensor 2 is pretty much all over the place. Am I on the right track? The vacuum holds steady, battery (AGM) is maybe 3 years old but shows 14V, fresh(ish) air filter, throttle body cleaned maybe 2 years ago, no codes (stored or pending) and passed emissions 8 months ago. Haven't looked at fuel pressure...

Here are some more sporadic readings of the Sensor 2 at idle.

 

[tworley]

Found this while researching 02 sensor readings...

" The post-cat exhaust gas mixture should be CONSTANTLY low in oxygen if the cat is doing its job of burning excess fuel. Therefore, the post-cat O2 sensor signal should be a constant lower voltage reading (not oscillating). So, if the post-cat O2 sensor is seen to oscillate just like the pre-cat O2 sensor, that means that the post-cat sensor is seeing the same gas mixture as the pre-cat sensor meaning that the catalytic converter isn't doing its job of burning excess fuel. The computer monitors the post-cat sensor and compares it to the pre-cat sensor. If the signals are similar, it assumes the cat is bad."

The readings I am getting appear to be oscillating and more. Interesting note--we received a recall notice in the mail for this jeep regarding catalyst efficiency. I wonder if that is what I am experiencing

 

[tworley]

Cleaned the throttle body again, not bad, not great.

Fuel trims.