I see DTC's for Sensor 1, Sensor 2, and....... Sensor 3?

**97AutoXVette** · 03-25-2014

Removing the CAT and replacing with a ZZP Catless Downpipe. I am going to turn off the secondary 02 SES light but my question is why does a third sensor show up in the tune? Should I just turn off the SES lights for Sensor 2 and not worry about Sensor 3?

**dsmuts** · 03-25-2014

What are you using to tune?

**dsmuts** · 03-25-2014

There is no sensor 3 btw so no need to mess with it.

**97AutoXVette** · 03-25-2014

HP Tuners pro. I figured it was just in there as a standard option by chance but didn't want to go clicking things without checking.

**Fivefingerdeathpunch** · 03-25-2014

Anything rear o2 related just set to 3, no error reported.

**97AutoXVette** · 03-28-2014

Originally Posted by Fivefingerdeathpunch

Anything rear o2 related just set to 3, no error reported.

That won't make anything in the ECU freak out and throw off AFRs right? I thought I saw a post of some guy and a horror story about changing the rear O2 setting and then his AFRs getting out of wack. don't see how/why that would happen though...

**Fivefingerdeathpunch** · 03-28-2014

1997-2000 PCM's don't care one bit about what the rear o2 sensor says. It's only there to say that the cat is working and there or it's not.

I've turned off all related codes for it along with EGR stuff as I don't run either.