Code result
P2DE8
Cold Start Engine Coolant Bypass Valve D Stuck Open
Moderate severity
What it means
During cold start, the engine coolant bypass valve D is stuck in the open position. Coolant bypasses the warm-up loop.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Valve stuck in open position
highOne of the most commonly reported causes for this code — check this first.
Actuator failed
mediumA plausible cause — test and verify before replacing parts.
Carbon or debris buildup preventing free movement
lowLess common, but worth ruling out after the more likely causes.
Related help
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