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Home >> Mitsubishi >> 2003 >> Lancer Evolution >> Repair and Diagnosis >> External Pages >> Different car >> Section 30 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P0128: Thermostat Function >> Possible Causes
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Possible Causes

WARNING: This page is about a different car, the 2002 Nissan Maxima and 2002 Infiniti I35. However, it is still accessible from the selected car via links, so may be relevant.

Malfunction is detected when engine coolant temperature has not risen enough to open thermostat even though engine has run long enough. Possible causes are: