OFT Stage 2 but still getting O2 Sensor CE
 

Hi, I installed a UEL on my 14 FRS, and flashed the ROM with an OFT Stage 2 UEL ots tune. Everything was good at first, but over the last 2 weeks I have gotten four different check engine lights all pointing to issues with the second 02 sensor.

Things i have done:
Used OEM new gaskets on all exhaust components for header and overpipe.
Replaced 02 sensor
Verified torque on header to head
Verified torgue on header to overpipe

Drivetrain Mods:
HKS airfilter
1320 headers
1320 overpipe
stock front pipe
Manzo M2 catback

I was under the impression that the stage 2 tune eliminated the 02 sensor reliance. Is that not the case? Anyone else have this problem?

I don't have my laptop in front of me and am kinda drunk right now bu go to CEL's and see if p0420 is enabled.

I had the same issue. Just email a copy of the tune file you are using to customer support at openflash. They will fix it:)

If your getting cel codes relared to rear o2 sensor then it likely the sensor was damaged during header install

Or you may have exhaist leaks do you have ltft over 10%.

If you intake is stock then its very unlikly its a tune problem .


List of codes would help

what are the CEL's specifically. List them.

Error codes are p0139, p2097, p2098

The o2 isn’t damaged as it’s a brand new 02 sensor. Getting codes a day after install. Getting codes on other o2 as well.

I just reflashed my ecu with uel stage 2 again. I’ll see if maybe a bad flash

Try to undo everything

Here are two data logs. One before i reflashed and it was running like a dog (but no check engine lights). One after i just reflashed.

Bump. Still having the problem. Have replaced the o2 and new gaskets. Nothing keeps it from coming back.

Looks like the tune did not disable the CEL. Reach out to Shiv and have him look at this.

the tune disables the P0420, that's it. It does not effect the operation of either O2 sensor. One of them is not even an o2 sensor, it's an Air Fuel sensor.

Just because your O2 sensor is new, does not mean it is working right. Get it tested at a shop that can look at the output of the sensor. Also, it could be a case of damaged wiring.

I had the exact same problem, turned out to be an issue with the tune. Openflash modified the tune and now it works.

which 02 did you replace those codes are for rear 02. not the front 02.


If you removed the rear 02 completly that wont work unless you modify tune. the standard tunes just disable the cat converter check function, if you complety remove rear 02 you need to make other adjustments to tune

What calid are you using?