2002 BMW 525I 2003 BMW X5 2001 BMW Z3 Roadster Check engine light is on.

download 1. Use a scan tool to monitor the fuel trim numbers and the Mass Air Flow (MAF) sensor data stream grams/sec readings. Nominal values are 5 grams/sec at idle in Park, and >150 at Wide Open Throttle (WOT) and 5000 RPM, in gear. Some scan tools have a freeze frame feature, which is useful [...]