02/22/2026
2012 Toyota Yaris
Diagnosis: The customer bought this vehicle and it started blowing an EFI fuse. It would stop accelerating, and when turned off, it wouldn't restart. They replaced the fuel pump, injectors, and canister purge valve, and installed two higher amperage fuses, which is something that should never be done because it's dangerous for the engine to catch fire. The problem persisted. They brought it to me for diagnosis, and while checking the components powered by the EFI fuse, I visually inspected the wiring and confirmed that they had removed the catalytic converter and installed two spacers on the oxygen sensor "to trick the computer." The wiring harness was left without the insulation that protects it from rubbing against the chassis, and due to the movement of the exhaust, it rubbed against the chassis until it hit it, causing a short circuit and blowing the EFI fuse. I recommended that the customer install an original catalytic converter and oxygen sensor. Listo ✅️ ✅️
