How canI tell if ignition module fails on initial start up on 97 Chevy G3500. The vehicle runs great once started but engine analysis indicate engine is running too lean. Can you Please help?

To diagnose a potential ignition module failure on your 1997 Chevy G3500 during initial startup, listen for inconsistent or rough engine cranking, which may indicate a weak spark. Check for any ignition module-related trouble codes using an OBD-II scanner, and inspect for signs of overheating or physical damage to the module. Additionally, examine the spark plugs and wires for wear, as these can also contribute to a lean running condition. If the engine runs well once started but struggles initially, it may be worth testing the module's output voltage and considering replacement if it’s below specifications.