My wife was driving her 04 XJ8 waiting in traffic and the yellow engine light came on. We took the car to AutoZone and they read the codes P0457 and P1111. They supplied a printout of each but i'm not sure if they gave me the right info because the printout lists OEM Brand - General Motors on the P1111 slip and OEM Brand - Domestic on the P0457 slip.

P0457 : defective loose or missing fuel cap, Evap canister broke, hose cracked or not connected, purge or vent solenoid defective, va leak at engine.

P1111 : Open circuit to IAT - check connector, Failed IAT, Open circuit condition


These two seem unrelated to me if these decodes are correct.

Help!

 

P1111 is really just for information. It is flagged after DTCs have been cleared, and all engine management OBD diagnostic monitor drive cycles HAVE BEEN COMPLETED.

P0457 just seems to be fuel cap related on the X350. It needs to see the fault over two ignition cycles before it turns the yellow light on.