No white smoke at all and oil is fine so is the coolant, plugs look good too. But I am wondering if my old engine may have damaged it when it cracked and started blowing unburned oil straight out the exhaust. I know some dsm tuners only use the factory denso O2 sensor cus they say it is better then bosch but I am not sure. My factory downstream motorcraft O2 sensor is still working perfectly with 164k miles which is amazing to me.

ATX MTX swap, rear drum disc swap, drilled rotors, ported intake, optim throttle body, CAI, 7.5L MAF, adj. fuel regulator, longtube headers, underdrive pulley, no EGR, low inpedence bigger injectors, 2002 Focus Swap