Hello, Jason here to help. The P0171 System Lean code... Was there a P0174 code also? How many miles on the X-type? Do you have a scan tool yourself?
Sorry for the many questions, they do help.
I have a handheld tester and it only gave me the 171 code. It has 86,000 miles, the car seems to be running fine.
The single code P0171 indicates a lean condition on one bank of cylinders most often. A vacuum leak is the most likely cause. The passenger side of the engine is called bank 1. Look around for a loose hose, cracked hose, etc... If none are found, then the Intake Manifold O-rings are the likely cause. All vacuum leaks are easily found with a Smoke Machine. This fills the intake manifold with smoke and any leaks will show up. If your scan tool can show data also, let me know. Jason
I'll check it out and let you know, thanks. Are the intake o-rings very involved to change?
No, if I recall they are quite easy. Two screws and pull them out. They are located near each other, one for each bank of the engine. They are located in the intake manifold above the right side of the engine. The o-rings go bad and that could explain the code on one bank. W0133-1834447 is the part number, two are required. How about your scanner, if it offers data besides codes, let me know.