The 2019 Jeep Grand Cherokee's EcoDiesel can develop turbo wastegate rattle, creating an annoying noise that may or may not indicate a performance problem. Understanding the wastegate helps diagnose the issue.
Wastegate Function
The wastegate bypasses exhaust around the turbo to prevent over-boost. It uses an actuator that can develop play or wear, creating rattle during certain operating conditions.
Causes of Wastegate Rattle
Actuator Rod Wear
The rod connecting the actuator to the wastegate flap develops wear at the pivot points. This creates looseness that manifests as rattle.
Wastegate Flap Play
The wastegate flap itself can develop play in its pivot bushing, rattling against the housing during exhaust pulsations.
Heat Cycle Fatigue
Repeated heat cycling causes component expansion and contraction, gradually increasing clearances that lead to rattle.
Actuator Internal Wear
The actuator's internal diaphragm or mechanism can wear, causing inconsistent positioning and rattle.
Performance Impact
Wastegate rattle is often just noise without affecting performance. However, if the wastegate can't seal properly, boost control issues and P0299 codes can result.