Code result
P04A5
Exhaust Pressure Control Valve B Stuck Closed
Moderate severity
What it means
Same as P04A4 but the valve B is stuck closed - back-pressure stays high even when the engine should run with low restriction; risk of overheating or excessive fuel consumption.
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 closed due to soot or broken linkage
highOne of the most commonly reported causes for this code — check this first.
Carbon or debris buildup preventing free movement
lowLess common, but worth ruling out after the more likely causes.
Component wear with age - mechanical play
lowLess common, but worth ruling out after the more likely causes.
Related help
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