Fuggedupmazda

While at idle when cold. Rpm fluctuates from 1k to 1.5k rpm then cuts off after fluctuating a few times. Throwing code for lean at idle. Replaced O2 sensor. Checked intake and intake manifold for leaks. Gonna clean the mass air flow sensor next. Then probably gonna change the throttle body. Cleaned it already. Any suggestions if MAF doesn't work?

Burned

Smoke the engine to find vacuum leak. May be low fuel pressure also