Drivable short-term, but fix now to avoid damage.
This code means the engine computer sees the fuel metering control 'B' inside the diesel injection pump performing outside its expected range. In plain terms, the pump isn't delivering the precise amount of fuel the computer commanded, which affects how the engine runs. It often points to a worn or failing injection pump, a metering valve issue, or wiring and sensor problems, and repairs range from electrical fixes to pump service.
$250 – $1800
Varies by vehicle and root cause.
For short trips you usually can, but it's not a code to ignore. The fuel metering issue can cause hard starting and power loss that worsens, so get it diagnosed soon. If the engine is in limp mode or running very rough, drive gently and head to a shop right away.
It depends on the root cause. Wiring or connector repairs may run a few hundred dollars, while replacing or servicing the diesel injection pump can range from roughly $800 to $1,800 including parts and labor. A proper diagnosis first will save you from replacing parts you don't need.
It's on the more serious side. Because it involves the injection pump's fuel metering, it can leave you with a no-start or stranded vehicle if it gets worse. It won't typically destroy the engine overnight, but it should be addressed promptly.
Both involve injection pump fuel metering, but P0258 is the 'B' control circuit while P0257 is the 'A' control. They often appear together and point to the same pump system. A technician reads them alongside any related codes to pinpoint the failing component.