Post header install Mil elimination issues

[cdaw2001ES]

I need some help understanding this.
DO I add the elliminator to the Back o2 sensor, or the front.
How does this system work?? One need to show more volatge than the other??? Which one needs to be higher???

[Fishboy55]

<div class='quotetop'>QUOTE(cdaw2001ES)</div><div class='quotemain'>I need some help understanding this.
DO I add the elliminator to the Back o2 sensor, or the front.
How does this system work?? One need to show more volatge than the other??? Which one needs to be higher???</div>It goes on the back one. The front O2 sensor needs to read a lower voltage than the front. This is a common problem in Rustangs or with headers that aren't properly designed to work on OBD II equipped vehicles. If the front and rear sensors read the same voltage when the ECU scans them, it assumes there's no catalytic convertor and trips the SES light Or "malfunction Indicator Light", hence the name MIL Eliminator. Without getting all technical, basically you're tricking the ECU to think your car is emissions compliant.

Just a note about buying headers that need MIL eliminators, here's the disclaimer from PEP's website, the maker of the Mil Eliminator: MIL Eliminators are designed and manufactured for off-highway use only. Installing these parts on a vehicle that is used on public roads may violate U.S., Canadian, state, provincial, and/or local laws and regulations including (without limitation) emissions and requirements. Additionally, the installation of these parts may void your vehicle's warranty.

Chip

[cdaw2001ES]

thanks Chip, but I am looking for technicall info.
Like what the voltage should be (range) ?
Can I safely use the same info provided for Rustangs -- ie, are all o2 sensors basically the same????

[NRG]

Instead of getting the MIL thingy there might be a chance for you to move your O2 sensor behind your cat. Right now one is at the header and the other one is before your cat. Find a way to put that behind the cat should solve the problem.......

[cdaw2001ES]

Ok now I get it. I didn't look at the SM close enough, the rear c02 is BEFORE the rear Cat. So the pre cat did the job of dopring the voltage before, while the front 02 was before the pre cat, so the 02 in the header is grovy. So what I need to do - to keep the system intact and actually working. Is drill in and weld on a new bung, extend the wires and move the sensor. OK, i can do that, Do I just put a stuby bolt in the old bung??

Maybe i can get the shop to just put in a new pipe when they put the Hiflow cat in.

Thanks for the info.