Fuel and air

P0248 — Turbo Wastegate Solenoid 'B' Range/Performance Fault

Severity: medium Drive with care, to a shop

What P0248 means

P0248 means the engine control module is not getting the expected result from wastegate solenoid 'B'. This solenoid normally meters vacuum or boost pressure to the wastegate actuator, which opens or closes the exhaust bypass around the turbo. When actual boost differs too much from target or the solenoid circuit misbehaves, the module sets the code and turns on the check engine light.

Symptoms

  • Check engine light on
  • Reduced power, especially under load
  • Sluggish acceleration or turbo lag
  • Hissing or whistling from the turbo area
  • Worse fuel economy
  • Limp mode

Possible causes

  1. Failed wastegate solenoid 'B'
  2. Open, shorted or corroded wiring or connector at the solenoid
  3. Cracked, loose or disconnected boost or vacuum control hoses
  4. Wastegate actuator or flap binding
  5. Leak in the intake path after the turbo
  6. Rarely, a faulty engine control module

How to diagnose

  1. Read all codes and freeze frame data, and note any other boost-related codes
  2. Inspect boost and vacuum control hoses for cracks, oil, or loose fittings
  3. Check the solenoid connector and harness for corrosion, chafing and poor pin contact
  4. Measure solenoid coil resistance and compare with the vehicle specification
  5. Check power and control signal at the solenoid connector with a multimeter or scope
  6. Use the scan tool actuator test to see if the solenoid clicks and responds
  7. Compare commanded and actual boost in live data
  8. Check actuator rod movement through its full range for binding

Common fixes

  • Replace wastegate solenoid 'B'
  • Repair wiring and connectors
  • Replace damaged vacuum or boost hoses
  • Repair or replace a binding wastegate actuator or turbo
  • Reflash or replace the control module if everything else checks out

Questions and answers

What does P0248 mean?

It means the ECU detected a problem with wastegate solenoid 'B' control: boost or the circuit signal does not match what was commanded. The solenoid, wiring or hoses are the usual culprits.

Can I drive with P0248?

Briefly and carefully, yes, but the engine may go into limp mode. Diagnose it soon to avoid turbo damage.

How do I fix P0248?

Start with the hoses and solenoid connector, then test the solenoid and check the wastegate actuator for free movement. After repair, clear the code and road test under load.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.