2003 Z
120k miles
No engine mods

I have smog this month and Im trying to get this fixed. My CEL has been on and I scanned the car and it was the downstream driver side sensor. After a few months my scanner would give me an error when I would try to check it. I took it to a shop to scan it and they said it had 4 CELs for all 4 o2 sensors.

Replaced driver side downstream sensor and CEL went away for a few minutes and key cycles, then came back.

Its understandable that they go out but all 4 at the same time?

The CELs are:
P0031 O2 Sensor Heather
P0051 O2 Sensor Heather
P0037 O2 Sensor Heather
P0057 O2 Sensor Heather
P0128 Thermostat Function


TO ANYONE THAT FOUND THIS THREAD IN THE FUTURE, I swapped the 15amp fuse in the driver side kick panel and everything is perfect. Drove 1500 miles and NO CEL. Funny part was, fuse wasnt blown but I swapped it anyways.

 

Checked the fuse box in the kick panel and 15amp o2 looked fine. Swapped it with another 15 amp, cleared the light and so far so good. Turned it on and off and drove it around the block.

 

Yep... 15A fuse #15 is the common. That one fuse is for all of them.