[Cdover73]

So i keep getting the P0152 code, O2 sensor bank 2 sensor 1 high input. I have changed the sensor recently and it went away for a while. Tonight while driving home it felt like the car dropped a cylinder or two and was running rough while losing power. However, i could press the throttle, regardless of the gear i was in, and it seemed to be a specific position of the throttle where it would pick up and run normal.

I have had an issue for a while where the car was running very rich for the same code. It was actually a lean condition being sensed, which was causing the right bank to dump in more fuel to compensate, resulting in a physically rich condition.

Does anyone have a clue what may be going on and why i keep burning through O2 sensors on the right bank? FYI, I have a Borla cat back, no cross over pipe, with high flow cats and the downstream O2 sensors deleted via MIL eliminators. No other mods to the engine or exhaust.

It almost seemed like water in the gas, or spark plugs fouling. And the only other code i get sometimes with the p0152 is an evap purge system faulty, which i also cannot pin point. I have heard a "woosh" sound when undoing my gas cap a couple times. But i dont know if the two are related.

Any ideas?? I am at a loss to the point i am actually considering selling the car. Im just not the type of guy to give my problem to others. Thanks in advance for all responses.

Cdover73

 

[Plumcrazy68]

What year is it? Did one a while back the pcm was going bad dumping fuel taking out cat.

 

[Cdover73]

Its an 03 with 65k miles.

 

[GTS Dean]

What do the plugs look like? Maybe you have a sticking injector. If you could look at the ECU block maps you might find an anomaly to lead you to the next step.

 

[Cdover73]

I havent pulled them yet. It just started last night on the way home from dinner and i was too aggravated to fool with it. I will pull them today and have a look.

 

[Cdover73]

It does act like a fouled plug. Or at least electrical. I find it odd that there is a spot in the throttle where it would kick in and pull normal. If i back off it noticeably loses power. But from that spot(a little more than halfway of the gas pedal travel) all the way to the floor it runs normal. Could it be my throttle position sensor, or something along that line? Or maybe a coil pack going bad and only giving full juice at WOT? Idk...shooting in the dark here so please overlook anything I say that sounds ignorant...lol!

 

[RobV]

O2 sensor gone bad again, pcm feed line, pcm signal line bad to O2 sensor?
Monitor the O2 voltages with a scan tool.
Check your cats with a IR thermometer.
Not sure on how quick the gen3 pcm is but fuel trim is determined by the delta between the up and down stream O2 sensors.

 

[Cdover73]

Would the downstream sensors being bypassed via MIL eliminator be causing a conflict maybe? I know the downstreams are feedback only and do not have voting authority, but they may cause a deviation in the delta enough to trigger the code? Again, just trying to wrap my head around it all.

 

[GTS Dean]

Check TB resistance and voltage for smoothness closed to open.

 

[ehiracheta]

clogged cats maybe?

 

[RobV]

Neither up nor down stream have voting rights. They are both readbacks. The delta between them is calculated by the ecu/pcm and used to determine setting like fuel. No idea what you using for the rear O2 as there are a number of ways people do this.

You need to check the O2 voltages/plotted curves. You can compare the 2 banks since you said that bank 2 is the problem but is assuming bank 1 is ok.

If you don't have heat shields on the headers, you can check each cylinder header tube with the IR temp gun. With the shields it just might be harder.

Start with the simple stuff. Checking the individual cylinder exhaust temp is quick, easy and will tell you if you have cylinder(s) running rich or lean.

 

[CEJohnson8300]

Fuuh. Am I going to run I to this when I put my high flow cat mid pipes and cat back on? Curious to know what the solution ends up being. Fwiw I don't think any of the ideas OP threw out as potential issues seemed unreasonable.
What does seem weird to my uneducated self is that an early '00s Dodge would base trims on the pre/post O2 delta but in my 2012 C class the post O2s are fully disabled and the ECU doesn't care. Dodge being Dodge I guess 😅