p0171 error code? e46 318i bmw?

before going on my holiday my car was very low on fuel, 10 miles left as computer picked up. put in 50.00 worth of fuel and treated system with fuel cleaner, after doing around 300 miles and using another 25.00 fuel with the car driving fine i left the motorway to have engine warning light come on?

ive had car on computer and has shown code 001 1 code 171 check fuel supply system, ecu code po170, been told possible injector failing of seeing cylinder low on reading one not going over 0ne, and two others peaking two going back next week but on return trip light didn't reappear. but since light has shown performance is definitely down, garage will check the system injectors i was going to replace the plugs but was told they wont get the light on.have had a quick check of maf boot the best i can without removing seems ok. ive just under half a tank left with with red ex treatment added as the cars driving ok but seems to be slightly down on power,should i continue and use the fuel up before re-booking at the garage as ive now done 30 miles without the light appearing, at a loss on what to do as i dont want to follow the practice of change this change that ,may be just panicking !! but feel if the cleaner has been doing its job it may clear itself or i should wait and see if light comes back on car drove better yesterday can i cause any problems continuing driving help me choose the correct path !!!!!!