O2 sensor help

[Lexstang]

I have a problem thats been driving me crazy. Cars been stumbling both idling, cruising and on takeoff. When I look on predator it shows 02s11 has 1 volt when warmed up, which as I understand is normal. however 02s21 barely has a trace, or no voltage. SO that means passenger side o2 is malfunctioning right? I replaced the passenger o2 and it didn't really improve. I pulled the 02 extensions off, since I have longtubes and used a voltage meter and all 4 wires from both sides show exactly the same resistance, so they are ok.

What is the problem? Am I totally stupid and it's actually the drivers o2 thats out? I can't switch them unless I break the alignment tabs off them. Any suggestions? Its very annoying that my baby isn't running 100% and I don't want to damage anything to boot. Any help would be appreciated.

[conley1000000]

Upstream or downstream?

[Lexstang]

Rear 02's are turned off via predator. So, to the point,upstream.

[conley1000000]

Hmm. then i dont know whats goin on there...

[Drivermod]

How bout the wires going into the factory harness. Not melted on the header or anything eh?

[Lexstang]

nope no melted wires. The connectors are behind the motor well away from the headers. By the way, I did find an easier way to connect and disconnect them. Take a long, but small bladed standard screwdriver and put it in the connector release. Works to get it apart but also to put it together. Its very tight space up there. I guess my next step is to take out all spark plugs and make sure they show good combustion especially equally to right and left banks. I certainly welcome some other responses.

Btw I've cleaned the IAC motor and the IAT sensors recently. That didn't really affect anything positively or negatively.

[95vertstang]

mine was doing the same but i replaced the 02's and my tps and the problem went away, do you think the egr could have any effect on this i dont know if any of those are you problem or not but just some suggestions i guess

[conley1000000]

Take your Predator and turn everything back to stock...then re test everything and see what happens then?

[Shortbus]

You should never see 1 volt on an 02 sensor. It should constantly fluctuate between ~.2v - ~.8v. Take a volt meter and get the 02 sensor voltage directly from the sensor on the signal wire. If it's constantly reading 1v, it's bad. If the computer sees 1 volt from the 02, it thinks the car is STUPID rich. It's going to cut fuel in an attempt to bring the voltage down.