Code result
P2594
Turbocharger Speed Sensor B Circuit Range/Performance
Moderate severity
What it means
Turbo speed sensor B is electrically intact, but the speed reading does not match the boost or air-mass model — same failure mode as sensor A performance fault, applied to the second turbo.
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
Oil-contaminated sensor tip
highOne of the most commonly reported causes for this code — check this first.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Sensor mounting loose - signal damping
lowLess common, but worth ruling out after the more likely causes.
Related help
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