Code result
P04A3
Exhaust Pressure Control Valve B Intermittent
Moderate severity
What it means
Same as P049F with intermittent or erratic feedback - typically a connector or harness fault.
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
Intermittent contact at connector or terminal
highOne of the most commonly reported causes for this code — check this first.
Connector with intermittent contact under vibration
lowLess common, but worth ruling out after the more likely causes.
Harness routed against vibrating component
lowLess common, but worth ruling out after the more likely causes.
Related help
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