Each month in Diagnose This! we present a real-life service scenario with clues as to what the ultimate diagnosis was. If you think you know the answer, be the first to e-mail [email protected] with the correct response for free Truck Parts & Service merchandise. The answer will be revealed in a future issue of the magazine.
Vehicle: 2005 IH 4400
Key components: DT466 engine with exhaust gas recirculation (EGR), Allison transmission
Scenario: This truck fails to restart only when the engine is hot. When the engine is cold, it cranks excessively but eventually will start. Once warmed to operating temperature, if the engine is shut down, it cranks but fails to restart. The problem started as a hard, hot restart and gradually would no longer restart at all when hot.
Clues: Refer to the screenshot of scan data that was captured when the engine was hot and cranking, but not starting. It did not start during this attempt.
