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Help with Codes P161F and P114D

10K views 6 replies 3 participants last post by  Iceman2011 
#1 ·
I have researched both codes and come to the conclusion, I need to replace one of my throttle actuators and my Bank 2 sensor 1 O2 sensor. As I researched there was some talk about the P114D there was a lot variables on that code. Anyone have experience with this code. To be clear this is the O2 sensor on the LHD driver side after the manifold catalytic convertor that needs to be replaced?


Thanks for reading.
 
#2 · (Edited)
P114D is related to the PRE cat sensor, driver side (bank 2). It reports a plausibility issue on the post cat but that is caused by a DME regulation issue using the pre cat sensor. It is either regulating rich too long or lean too long.

If you were to monitor the post cat sensor voltage you will see its voltage output popping back and forward between 0V (rich) and 0.7V (lean) at operating temperatures. That is good behavior as the DME is trying to keep the fuel to air mix to 1:14.7 (stochiometric) by measuring with the pre cat sensor and adjusting fuel injection angle and air intake. The post cat is very sensitive with respect to the lean/rich threshold and pops high and low by the slightest surpassing of the threshold in either direction. The DME expects this popping high and low. However it it sticks high or low for too long of a time and the 02 sensor check is run at that time, you may end up setting P114D.

Is it consistently popping up after every day rides or only on long spirited drives? Have you cleared it a couple of times to see if it comes back fast or only after a long time? I would recommend to study its behavior a bit. The sensors are 250 bucks a pop. Patience pays off.

Before you replace it make sure you do not have any vacuum (intake) leaks and exhaust leaks as either of these disturb proper DME regulation: Too much air enters through an intake leak post the MAFs or exhaust leaks throw the O2 sensors off. The O2 sensor measures the O2 content in exhaust gas against ambient O2 rich air. If the O2 is surrounded by exhaust gas outside of the exhaust du to lack of O2, it won't work properly and likely reports rich.

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#3 ·
RT, thanks for the response. It comes on consistently after about 100 miles, usually it will show up in the handheld within 10 minutes, but not on the dash until later. I have checked for vacuum leaks none that I can see or hear.


So I will replace the PRE cat sensor on the header. If it still shows up I need to replace the post cat sensor also?
 
#4 ·
The DME checks the O2 performance twice before it calls it a fault. So at least 2 drive cycles of sufficient duration and speed such that it can test it. The DME needs the engine running for at least 18 min and the test is done above 60 km/h.

Once the code is set you are likely to get a subsequent cat efficiency error as well, but that is not real until you positively replaced your 02 sensor(s) first with good ones. I would go for the pre cat first and see what happens.
 
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