Chevrolet Astra 2002 P0170 Fuel Trim Issue: Car Turns Off After Warm-Up
Hello, I'm working with a 2002 Chevrolet Astra at my job. We're experiencing a problem where the vehicle starts but shuts off once it reaches normal operating temperature. The OBD2 scanner shows a P0170 fault code, indicating a lean fuel condition. The engine control module is attempting to compensate by increasing fuel delivery through the fuel trim system, but this isn't resolving the issue. What steps should I take to diagnose and fix this problem? Any advice on common causes or diagnostic procedures would be greatly appreciated.
No other fault codes are present — that's notable. P0170 typically indicates a lean condition, where the fuel trim system is adding more fuel to compensate. Check fuel pressure, look for vacuum leaks, and verify the MAF sensor readings. If oxygen sensor readings show consistently low values, try spraying carburetor cleaner into the throttle body to see if the O2 readings improve. A reasonable guess: fuel pressure might be too low.