A Vauxhall Astra 1.6 CDTi in Norwich with recurring EGR fault codes, poor driveability, reduced efficiency, and intermittent MAF-related faults. At face value, this could easily be mistaken for a failed MAF sensor. However, fault codes don’t always identify the root cause — they indicate where the system sees a problem. At EA Tuning Essentials, we diagnose the system properly before replacing parts or applying software. Diagnostic Process Before any changes were made, we carr