Magnum Swap, which 02 sensor to use, pre-cat or post-cat

jbc426 said
I went through this when I set up my factory EFI on my 1999 OBD2 system, and used the pre-cat sensor for the closed loop metering.

I also hooked up an electronic cat simulator to feed an artificial post-cat signal to the computer to not have it throw a code and go into limp mode. However, I'm not sure not having that signal would have thrown it into limp mode. It may have just turned on the check engine light and continued to run as programmed.

You can always call SOLO PCMs in Florida, which is where I got my ECM with no security and set-up for a manual trans car, as I run a 2004R. Another great resource for SCT Tuner custom programming is Chris at Performance Injection Equipment.

https://www.performanceinjectionequipment.com/

Hey thanks for adding input as I have followed a lot of your stuff! The engine is up and running with just the pre-cat. Smooth as silk!! I owe a TON to this site and a guy here who went OUT OF HIS WAY to coach me through this. I have not driven it yet, but hope that my 97 does not go into limp mode, will find out soon, from what I have read it looks like starting in 98 security features were added so crossing fingers! I can deal with a check engine light for the time being but nice that you shared resource in Florida if I need it!!!!