I have a 95 7.4 I transplanted into a camaro and I was wondering when does it goes into closed loop mode and if it ever runs closed loop at idle? My O2 value barely jumps from .45x to .47x at idle and revving it. Is this normal? On my 97 it has huges swings from .0xx to .7xx at idle.

Also, I have the CATS tuner program and there are a couple of option that has "open throttle" and "closed throttle" screens, what exactly is the difference? Is closed throttle mean idle or when you let off the gas?

Thanks,

Lee

 

in closed loop the o2 values should swing like you described, when i run open loop in my car, that is when the o2 values remain in the .45 range.

you might check to see what the settings for closed loop enable are set to in your bin. there are also a few BLM enable values , you might check those out too.

depending on your datalogger you should be able to check the closed-loop flag, to see if you are in closed-loop or not.

 

The read out shows open loop, that's why I was wondering if/when it goes closed at idle.

The CATS software does not show me anything as to when/how the closed loop is enabled. I was hoping it gave me access to more information but it doesnt.

Lee

 

you would have to look at the constants in the bin, there is a min closed loop temp setting, i had a problem when i put a 160* t-stat in, my car never got warm enough for it to enter closed-loop, i lowered my CL enable temp to 140* , problem solved.

 

mine goes closed loop at about 157 deg with a 180 therm. i believe open loop idle allows you to command A/F ratio at idle outside of the choke effect. i dont think there is any issue with open loop idle all the time as long as settings are appropriate for your engine.. i guess with some of the larger cams running open loop is considered.