But repair is also pedagogy. Marcus explained to the owner—a woman whose commute folded two cities into one sleepless routine—that a hot injector is rarely the only malcontent. Fuel quality, maintenance rhythms, and the quiet betrayal of corroded connectors all played parts. He advised a short list: clean the rail annually, replace O-rings proactively at the first sign of hardening, keep the electrical connectors free of moisture and dielectric grease-friendly, and watch for voltage anomalies. He said it simply; the owner nodded, the cost less a surprise than a small calculus of prevention.