Just measured one .............. 323 Ohm ................ I run without it but only because i don't like the figures it trys to pull when in closed loop mode. It's always seeking best economy and lean A/F for emssions wheras I'm purely chasing the performance side of things and also dyno time to fine tune light throttle is of no issue to me either. Once again I think it's just personal preference and once into open loop mode ............ its only extra weight