A method for monitoring an internal combustion engine (1') having an injection system, in particular for preventing dieseling in the case of a diesel engine, comprising the following steps: Establishing a theoretical calorific balance of the internal combustion engine (1') and determining a diagnostic signal (.DELTA.H) reflecting the disequilibrium of the calorific balance, the diagnostic signal (.DELTA.H) indicating a fault in the injection system and/or the internal combustion engine (1').