i had alot of problem with my car recently ,

i had an error, and the garage, recommended fuel filter replaced,
problem still there, so asked to replace the air fuel ratio sensor,

which i did, and i thought at the same time i replace the fuel pump to a walbro fuel pump.

now a new error,

the car JUDDERs at different speed and different gears,
its lost power, feels like a 100bhp car now :.(

cos i'm away from any garage this week , i ordered a obd scanner,
and i got the error code

P0171


System Too Lean (Bank 1) - usually caused by a leak in the intake system somewhere between the Mass Air Flow sensor and the cylinder intake valves. Look for a vacuum hose that’s become disconnected or a crack in one of the tubes connected to the turbocharger


can someone explain this to me, and how to repair it, and costs???

 

Did the loss of power/juddering occur after fitting the walbro ?
If so, i would start by looking at the pump you fitted (connections/pipes/pick-up clear of obstructions).

What was the original problem you had with the car ??

 

original problem was stuttering at cruising speed,

don't remember what the code was at that time, but i was told it was the air fuel ratio sensor that might need changing,


the new problem occured when i fitted both fuel pump AND AFR sensor