Trace the harness all the way back to the PCM. I'm wondering if the heater circuit for the O2's is common somewhere along the harness, making it possible to have the bleed Injuneer mentioned...

 

I disconnected the heater wires from the o2 and the numbers are much better and the car is running much better except at idle. The o2 numbers have the variance from 0-0.9v.
It still has a nasty stumble because of a really rich condition. i cant figure out why. Again it does not have that stumble when the car is in open loop only when in closed loop.

I noticed the fuel trim cell goes up to about 16 or 18 when idleing and the charcoal canister purge duty cycle has no reading. When the charcoal canister purge duty cycle percent is around 11 fuel trim is 6. Seems like whenever there is a reading on the ccpdc the fuel trim is much lower. Im not sure if this has anything to do with it but i figured id mention it.

 

The fuel cell # is determined by a grid of RPM and engine load (MAP). It is not determined by the EVAP purge duty cycle. It's the other way around - the EVAP purge duty cycle is probably triggered by the RPM/MAP combination.

For an overview of the PCM's air/fuel control, read the air/fuel control section of this:

http://www.injuneer.com/ScanMast.html

 

Thanks i read that it gives me a good understanding of how everything works. Im gonna work on figuring out my problem and i'll post back results incase anyone else has a similar problem.

 

I downloaded your DataMaster file, but its on my PC at work. I looked at it briefly. I'll take another look at it Monday.

 

thanks I appreciate the help

 

My IAC pos counts at idle are at 125 and as high as 145 does this seem right...
The article that injuneer gave me to read said they should be between 20-40 counts at idle. Could this cause my rich problem...