O2 problem

[STR8BALLN]

O2's will not switch. The guy had Bosch's at first, we swapped them out for Denso's. When you start the car, they stay around 400's. Once the car warms up they will go to 500's. Then if you hold the throttle for a while they will go to 600-700 but they stay straight, they never switch.

We checked the grounds.
Swapped to the rear O2 plug to make sure the plugs were not crossed.
Changed O2's with 2 different brands.
Swapped sides with the O2's
Bought and tried 2 different O2 extentions( ebay and racetronix)



Maybe you guys see something I don't.

[JHPerformance]

Pull up a pinout sheet for your PCM connectors, find your B1S1 AND B2S1 PCM pins and check continuity with a multimeter to each of the 4 wires on both sensors. That will eliminate the wiring issue, O2's pink wire is ignition 12v(check with key on) or probe the wires to your fuse box.