2001 Dodge Caravan Engine light on

Engine light problem indicated a small vacuum leak between gas tank and emission canister. Mechanic said 99% of the time it's a gas cap. Repl cap, 1 week later light came back on. Computer indicated same problem. Found one cracked vacuum line at front emission canister, replaced. Light cleared. Drove for 15 minutes, turned off engine. Restarted engine one hour later, light came back on. Further research found another cracked line at rear emission canister, replaced. Computer tester won't clear light, now states Internal Control Module Failure. HELP
Carrol