Stumbling when cruising

[RiGs2G]

My Talon recently started stumbling when cruising. The O2 voltage seems to not cycle anymore, either and is at .75 or so at 3000RPM. The car struggles to maintain 60mph when cruising. If I give it a little gas to pass someone, it spudders and doesnt go anywhere. When I floor it, everything seems fine and it pulls just as hard as it used to. If I give it a little more then 50% throttle from idle it stumbles and then once 3500 RPM hits it pulls like everything is ok. It does this after the car is warmed up. When its cold the O2 voltage cycles normal and everything seems ok. I swapped out the wideband O2 sensor(zeitronix running the computer), plugs, and checked the fuel pressure, none of that helped. Thanks for any help you can provide.

Mike

 

[Kid4g63]

Have you checked the voltage on TPS to be sure it's good?

 

[RiGs2G]

My SAFC shows that the TPS is working fine. I would think that if it was the TPS then the O2 voltage would still cycle?

 

[mschlanglv]

Most surging problems are related to running lean. Can you explain your O2 situation better? You mention switching and then a wideband. Do you use both, and emulator, or ? Widebands don't cycle like a narrowband will, so knowing which one you have will help in diagnosing.

 

[RiGs2G]

I have the zeitronix wideband simulating the narrow band. I can watch the O2 voltage on my Apexi Turbo Timer(which reads off the ECU/narrowband). It always cycled before this. I need to hook my laptop up and see exactly what the wideband is doing when cruising.

 

[tjbiker031]

I have the zeitronix wideband simulating the narrow band. I can watch the O2 voltage on my Apexi Turbo Timer(which reads off the ECU/narrowband). It always cycled before this. I need to hook my laptop up and see exactly what the wideband is doing when cruising.

 

[RiGs2G]

Just going back and updating: I changed out the wideband O2 sensor and after a couple days the car started running fine again. I think the other wideband was on its way out. Thanks for all the help