This phenomenon describes a gradual, uncontrolled rise in manifold pressure within a turbocharged engine, exceeding the intended or pre-set limit established by the boost control system. It typically manifests at higher engine speeds and throttle positions. For instance, even with a boost controller set to 10 PSI, the pressure might climb to 12 or 13 PSI as the engine approaches its redline. This is often attributed to limitations in the wastegate’s ability to effectively bypass exhaust gases from the turbine housing.
Understanding this occurrence is crucial for maintaining engine health and performance. Excessive manifold pressure can lead to detonation, potentially causing severe engine damage. Furthermore, it can negatively impact the consistency and predictability of power delivery, undermining the intended performance gains from the turbocharger system. Historically, addressing this issue has involved modifications to the wastegate, turbine housing, or exhaust system to improve exhaust flow and alleviate backpressure.
