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Replaced O2 Sensors

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I replaced my front O2 sensors yesterday because I kept getting a P0155 code. The ARH headers had the sensor bungs horizontal, rather than angled down at least 10 degrees from sensor manufacture recommendations. Seems like the moisture gets trapped inside the sensor over time leading to failure. The 10 degree angle allows moisture to drip out. Of course this isn't an issue with the original manifold because I believe they are almost pointing down.

Nevertheless, I had a shop make new holes, install new bungs, and cap off the old bungs, before installing the new sensors. The CEL is gone for now, but we'll see how it plays out. My first CEL was a couple days after the LT install, but it was a different code, for cat efficiency, which wasn't really a concern..since i have no cats. About a month into driving (1500-1600 km's), I then got the P0155 code.

Attached is a photo of the sensors that came off. The orange-ish sensor is from Bank 2 (driver's side) and is the sensor that failed. I am going to contact sensor mfg's to figure out what the colour means. Usually orange means additives, and the only additive I added was Sta-Bil over the winter when the car wasn't used. Other than that, I am using Petro Canada Ultra 94. Im just curious as to why only this side is orange, unless the orange was just the wide-band O2 (with heating circuit) going out with a bang because of the moisture. Im saving Bank 1's sensor as a spare in-case I have further issues (hopefully not).

I also got rid of my extensions after I un-clipped the harness from the top of the transmission and had enough slack to not only comfortably get to the original ARH sensor locations but also my new locations which are about an inch downstream of the ARH locations.

DSC_0326_zps32bcf4b8.jpg

Thanks to anyone who gave me input over the last couple weeks while I was dealing with this issue.
 
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Since we are running an identical set-up, I'm starting to think that I have an exhaust leak since I only have P0430 and not P0420 also. Going to need my bolts checked....awesome!
 

Justin

Save the dawn for your dishes!!!
i reused all but one factory stud and nut. there was only one spot that was to tight for the stud to remain in place. i prefer the factory stud and nuts as they dont tend to back off that easily cause they are the "squished" nuts
 
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Bama said my tune also had the rear O2's shut off. They told me to go down to the 92 octane tune, but the P0430 is back on again. I was thinking it might be a exhaust leak, but if the sensors are off, then they wouldn't trigger from a leak with the extra oxygen flowing in.

Another interesting thing I noticed is my measured AFR using SCT's LiveLink. The measured AFR is 0.00 or some insane negative number but mainly 0 as if its not working, and this is for both banks. However, I do see a sinusoidal wave with the y-axis with all zeros. For the most part both banks are close, but there are random spikes.

My air/fuel gauge in the dash is reading though and at idle goes from 13.5 to 14.5 and on throttle 13.9 to 14.1. Anyone know where this guy picks up the measurement?
 

Justin

Save the dawn for your dishes!!!
sadil said:
Bama said my tune also had the rear O2's shut off. They told me to go down to the 92 octane tune, but the P0430 is back on again. I was thinking it might be a exhaust leak, but if the sensors are off, then they wouldn't trigger from a leak with the extra oxygen flowing in.

Another interesting thing I noticed is my measured AFR using SCT's LiveLink. The measured AFR is 0.00 or some insane negative number but mainly 0 as if its not working, and this is for both banks. However, I do see a sinusoidal wave with the y-axis with all zeros. For the most part both banks are close, but there are random spikes.

My air/fuel gauge in the dash is reading though and at idle goes from 13.5 to 14.5 and on throttle 13.9 to 14.1. Anyone know where this guy picks up the measurement?
there are a few options to monitor the A/F in the sct livewire data logger. i think you selected the wrong one. I dont have mine to look at right now to tell you what to select. have you contacted bama about the codes? I am not saying its this but bama tunes are well a little to be desired. havent found anyone that has had them that tried say AED or Lund that went back to their bama tunes....
 
sadil said:
Bama said my tune also had the rear O2's shut off. They told me to go down to the 92 octane tune, but the P0430 is back on again. I was thinking it might be a exhaust leak, but if the sensors are off, then they wouldn't trigger from a leak with the extra oxygen flowing in.

Another interesting thing I noticed is my measured AFR using SCT's LiveLink. The measured AFR is 0.00 or some insane negative number but mainly 0 as if its not working, and this is for both banks. However, I do see a sinusoidal wave with the y-axis with all zeros. For the most part both banks are close, but there are random spikes.

My air/fuel gauge in the dash is reading though and at idle goes from 13.5 to 14.5 and on throttle 13.9 to 14.1. Anyone know where this guy picks up the measurement?

P0430 is a CAT efficiency code. What you need to do is use a scan tool and check monitor status. Your CAT monitor should be listed as "unsupported" or NA. If not, you need to get a tune that has the CAT monitor "shut-off". A/F ratio is calculated using the front O2 sensors. Rear O2 sensors are used to determine if the CAT is working properly.
 
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Justin said:
there are a few options to monitor the A/F in the sct livewire data logger. i think you selected the wrong one. I dont have mine to look at right now to tell you what to select. have you contacted bama about the codes? I am not saying its this but bama tunes are well a little to be desired. havent found anyone that has had them that tried say AED or Lund that went back to their bama tunes....

I understand what you mean but I need to get my AFR reading so Shaun @ AED can look at my logs. Without them, I dont think he'll accept my log.

06mach1 said:
P0430 is a CAT efficiency code. What you need to do is use a scan tool and check monitor status. Your CAT monitor should be listed as "unsupported" or NA. If not, you need to get a tune that has the CAT monitor "shut-off". A/F ratio is calculated using the front O2 sensors. Rear O2 sensors are used to determine if the CAT is working properly.

Thanks 06mach1, can you please give me further details regarding how to check monitor status. Which scan tool do I need?

I would also like to add that @ WOT, my AFR is around 12.
 
sadil said:
Thanks 06mach1, can you please give me further details regarding how to check monitor status. Which scan tool do I need?

On my OTC scan tool, monitor status is the first screen you see once the vehicle info is entered and the scan tool has acquired data. Other scan tools might list under inspection data. Any newer scan tool that reads CAN protocol would read monitor status on the Boss. Monitor status is used for OBD emissions inspections, among other things.
 

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