What it means
Same as wastegate A stuck closed, applied to the second wastegate. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Wastegate B regulates exhaust flow through the second turbocharger or boost stage; when it stays closed, exhaust continues driving the turbine and boost can rise beyond the requested level. The control module compares commanded boost with manifold pressure and sets this code when the pressure response indicates wastegate B is not opening as commanded.
Common causes
Most likely first.
- Carbon-locked wastegate flap
- Carbon or debris buildup preventing free movement
- Component wear with age - mechanical play
Symptoms
- Check-engine light may come on
- Reduced engine power or boost may occur
How to diagnose it
- Use a scan tool to save freeze-frame data and compare commanded boost with actual manifold pressure when the code set.
- Inspect wastegate B’s flap, linkage, and actuator for carbon deposits, debris, damage, or a disconnected part that could keep the flap shut.
- With the engine off and cool, check whether wastegate B’s linkage moves freely through its intended travel without binding.
- Inspect wastegate B’s actuator hoses, wiring, and connectors for damage, leaks, or corrosion, keeping its parts distinct from wastegate A’s.
- Test wastegate B’s actuator and control circuit according to the manufacturer’s procedure and confirm that it responds to commanded movement.
Common fixes
- Remove carbon or debris that prevents wastegate B’s flap from opening.
- Repair or replace a damaged or leaking actuator hose serving wastegate B.
- Repair damaged wiring or corroded connectors in wastegate B’s control circuit.
- Replace a seized or worn wastegate B actuator, flap, or linkage as indicated by testing.
Can I keep driving?
Avoid heavy acceleration, towing, and high engine load until the fault is diagnosed, since a closed wastegate can cause excessive boost and engine damage. Stop driving if the engine loses power suddenly, makes unusual noises, or shows other signs of a serious problem.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.