my 99 rx300 has 160,000km,first P171,I changed new MAF sensor from ebay cost me $100, then P171 came again and P1130(it should show you bank one or tow failure, that means O2 sensor dead), I changed two O2 sensors from dealer cost near $700, now it's OK,my bank two O2 sensor also is dead which near exhaust pipe,but now it's ok no error code show, I will change late if it show error again.