Mercury

I have a 95 mercury grand marquis. i did a diagnostic and found the trouble code which read "system to lean (bank 1&2)". what does this mean?

Somethiing in the fuel control system is wrong causing both banks of cylinders to be lean, generally this rules out injectors, plugs, wires, o2 sensors, ect since it is happening to both banks. your problem is either a bad maf sensor, fuel pressure too low because of a pump, clogged filter or bad regulator or a possible vacuum leak into the bloke ifold. this engine has a rubber t in the vacuum line from the pcv valve on passenger side of the engine, these have a habbit of cracking causing this concern.