I am having a really stange problem. My o2 sensors the pcm uses are in my cross over pipe. My setup is very similar to realquicks log manifolds. The problem I am having is that my PCM thinks my car is pig rich and is pulling fuel to the point where the car drives like crap.

My wideband is in the down pipe after the turbo and it reads fine. I even stuck the wideband into the cross over in place of one of the pcm o2s and it ran fine. So I know that passengerside bank is not rich.

Any ideas? I am trying to use VE master to do a speed density tune, but I am ending up with the opposite of what I want.

 

try changing the sensors first

 

The sensors in there are new. They are an aftermarket brand. But I also tried a set of GM sensors and they read the same.

 

whats the 02 mV reading from the pcm?

whats the wideband reading?

 

When it starts pulling fuel the wideband will go up to the neighborhood of 19 or 20:1 and the pcm is seen 900s mv from the o2s

 

Check all the wiring closely and make sure you don't have any exhaust leaks.