So some of you may know I just recently installed a set of headers on my cherokee. When I installed them I decided to move my wideband from the passenger side down pipe to the drivers side where my narrow band is. So I installed the headers, and installed a short collector (seen here: http://www.gearhead-efi.com/Fuel-Inj...and-o2-sensors )
So I decided it was probably a good idea to do another free air calibration on it before I installed it. I followed the innovate instructions, powered up the mtx-l with the sensor unhooked, left it on for over 30 seconds. Turned it back off, hooked up the sensor, turned it back on, it went through its normal power on flashy lights, then the heater, then it calibration, then to the upper limit of 22.4 (like its supposed to do) I then turned it back off, installed the sensor in the exhaust, and fired it up. Well no dice, its stuck at 22.4. I turn on the ignition, it comes on like normal, I start the engine, it heats up, then when it would normally start displaying afr, it just jumps to 22.4 and stays there. I test drove it and it never changed. I let it cool, un hooked it, removed it, did another free air calibration, but no change. wtf? All I did was install headers. Its been working flawlessly for the past two years, I install headers and now it wont work? I checked, and double checked all my wires, the cable going to the sensor, etc. I can find nothing wrong.
I called innovate today and the guy I talked to said there is nothing wrong with it, and that its a semi common issue. He asked how I had it powered, and that was my problem. I have a 30 amp relay powering one side of a small 4 gang fuse panel I mounted under the dash. 1 fuse powers the ecm, the 2nd powers the injectors, the 3rd powers the heating element in the narrow band o2, then the 4th I have powering the MTX-L. He said it should not be like that, and should be on its own relay straight from the battery with nothing else hooked to that power wire. I told him its been working perfectly fine like this for a couple years, he said it didnt matter, it was wrong and that was my problem. He said something happened to make it recalibrate when it was in the exhaust with the engine running. He said to re wire it to have its own power relay and then recalibrate it, and it would work.

I'm kinda skeptical, but I am going to take him for his word, I have plenty of relays and wire, so it wont be to hard to add another one. But still, why suddenly did it decide to not work? Anyone have any ideas? Ever seen something simillar? I asked about the headers being coated, and different gaskets could have caused a different ground path, he said no as its grounded through the wires/guage and not the exhaust.