bank 1 lean code p0171

Question

Now that I've found the code how can i pin point the problem it is a 2004 f150 5.4 engine. Tank you

Answer 1

P0171 Lean system bank 1

Vacuum leaks are the number 1 cause of lean bank , check the brake booster hose, for any vacuum leak especially along the hose, or any vacuum lines that has disconnected