P0258: Injection Pump Fuel Metering Control B Low (Cam/Rotor/Injector)

These codes cover the electrically controlled fuel metering actuator on a diesel injection pump – on common rail usually an inlet metering valve on the high-pressure pump that sets how much fuel is compressed. P0258 means the actuator B circuit reads low. The only manufacturer found, Saab with its 3.0 V6 diesel of the early 2000s, uses it not for a second valve but for the shared supply of both metering valves: a short to ground or open for more than about 1 s triggers limp mode with limited pedal response and injection quantity, rail pressure capped at 60 MPa and idle raised to 1,000 rpm; the warning light comes on if it recurs on the next trip.

Medium severity. Can I keep driving?Drive as little as possible and go to a repair shop. If you smell fuel or the engine is shaking badly, do not keep driving.

Symptoms

Check engine light on (after the second trip)
Loss of power, limp mode
Raised idle speed in limp mode

Most likely causes

Supply wire, fuse or relay of the metering valves open or shorted to ground
Connector at the pump corroded or loose
Metering valve shorted to ground internally
Engine module

What to check, in order

Start with the simplest. You can tick off each step.

Check the connector and wiring of the injector indicated
With the connector unplugged, check whether the signal wire is making contact with ground.
Measure the resistance and compare it with the manufacturer's specification
Check the control signal with an oscilloscope; on direct injection or diesel engines, leave this to a repair shop because of the high voltages
On diesels, check the per-cylinder injection corrections

Good to know

Repair difficulty: medium
It can trigger limp mode.
It affects emissions.

What each character of P0258 means

P: Powertrain: engine and transmission
0: Generic code: same on every make
2: Fuel injection
58: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0258?

Drive as little as possible and go to a repair shop. If you smell fuel or the engine is shaking badly, do not keep driving.

What causes code P0258?

The most common causes are: supply wire, fuse or relay of the metering valves open or shorted to ground; connector at the pump corroded or loose; metering valve shorted to ground internally.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.