Secondary O2 sensor needed for Cruise control?

[hirollaz]

I'm having the same issue, running catless UEL header, Ecutek tune, my CEL light came on with cruise control being used. CEL does disable the cruise control. My code was P0137, low voltage secondary o2.

[FR-S Matt]

Originally Posted by hirollaz

I'm having the same issue, running catless UEL header, Ecutek tune, my CEL light came on with cruise control being used. CEL does disable the cruise control. My code was P0137, low voltage secondary o2.

You need to have the secondary O2 disabled through Ecutek. The only one that should be used is the primary.

[DJCarbine]

Just an update, ecutek tune can disable the dtc if you have no secondary o2 sensor, just ask your tuner

[Jasiel9653]

Originally Posted by DJCarbine

Backstory first...

Removed my secondary O2 sensor from my Borla UEL and installed a wideband sensor in its place. I have an ECUTEK tune, so I figured that the secondary oxygen sensor checking is removed and I thought nothing of it.
The next day I start the car and begin to drive. The CEL comes on after a few minutes, and when I press the cruise control on/off switch the cruise control light comes on but will NOT turn off. The wideband is also reading a rich air/fuel ratio (13.2) at idle when the car should be in closed loop (fully warmed up etc.)
Its almost as if its stuck in open loop or some sort of catalyst self-test mode where it runs rich at idle and doesn't use primary O2 sensor to trim fuel

WOT shows normal A:F of low 13's so I believe the wideband is getting accurate readings.

Does the ECU need the secondary O2 hooked up for some reason?
I know there was a thread stating that you don't need the secondary (as is common on older OBD-II cars), but it is creating some strange problems for me.

Anyone with any input?

I had the same issue i had some dc sports headers installed and nothing happened i drove for like a month and then i was on the highway and ia had my cruise control on and it shut down and the check engine light came on.I took the car to the dealer and they said it was bc of the o2 sensor so i heard that by installing a spacer on it you can fix the problem.