P0236: Turbocharger/supercharger boost sensor "A" circuit range/performance
The boost pressure sensor’s signal is missing, out of range or doesn’t make sense to the engine computer. Without a boost reading it can trust, it can’t control the turbo properly, and many engines limit the power.
Updated
What P0236 means
The boost pressure sensor measures the pressure the turbo builds in the intake. The engine computer uses it to control the turbo: with a wastegate or, on most modern diesels, with movable vanes in the turbo.
P0236 means the sensor’s reading doesn’t make sense to the computer. Without a boost reading it can trust, many engines limit the power, so the engine and the turbo aren’t overloaded.
On many engines the boost sensor is the intake manifold pressure (MAP) sensor. Read My Car’s live data shows the intake manifold pressure and the barometric pressure, if your car reports them. With the engine off, the two should read about the same.
P0235, P0237, P0238, P2263 and P2563: the sensor’s circuit and boost control
P0235, P0237 and P0238 are faults in the sensor’s circuit: no usable signal, too low or too high. The checks start with the plug and the wiring.
P2263 means the boost doesn’t follow what the computer asks for, too low or too high. P2563 is a fault in the sensor that reports the position of the turbo’s vanes. Both get the same advice as P0236; their own meaning and causes are shown below.
P0235: Turbocharger/Supercharger Boost Sensor A Circuit
P0237: Turbocharger/Supercharger Boost Sensor A Circuit Low
P0238: Turbocharger/Supercharger Boost Sensor A Circuit High
P2263: Turbo/Super Charger Boost System Performance
The boost pressure doesn’t follow what the engine computer asks for: it stays too low or goes too high. Many engines then limit the power.
Common causes: sticking turbo vanes, wastegate or their actuator, leaking boost hose or intercooler, or a split vacuum hose, faulty boost pressure sensor, restricted exhaust, such as a clogged particulate filter.
P2563: Turbocharger Boost Control Position Sensor Circuit
The sensor that reports the position of the turbo’s adjustable vanes, or its circuit, has a fault. The engine computer can’t control the boost precisely, and many engines go into limp mode.
Common causes: faulty vane position sensor or turbo actuator, wiring or connector fault, often heat damage near the turbo, turbo vanes sticking with soot.
Can I keep driving?
Drive gently
Drive gently and have it checked soon. Many engines cut the power (limp mode) when the boost can’t be measured or controlled, sometimes suddenly while accelerating, and boost that isn’t controlled can damage the engine. Avoid full throttle and overtaking until it’s fixed.
General guidance based on the code alone, not on the car’s actual condition. If in doubt, stop and ask a mechanic.
Limp mode can come on suddenly while you accelerate, so allow for it when overtaking or joining fast traffic. If the boost can’t be controlled at all, too much of it can damage the engine and the turbo: that’s why the engine computer cuts the power.
Symptoms
- A sudden loss of power when accelerating, or limp mode.
- Power that comes and goes, or a hiss or whistle from a leaking hose.
- The check engine light, sometimes only after hard acceleration.
Common causes
- Faulty boost pressure sensor. With the engine off, its reading should be close to the barometric pressure.
- Wiring or connector fault. Look for a loose plug, oil in the connector or damaged wires.
- Leaking boost hose or intercooler. Air escaping through a split hose or a loose clamp makes the boost fall short of what the computer expects.
- Sticking wastegate or turbo vanes. Soot can make a diesel turbo’s vanes stick, so the boost doesn’t respond as it should.
Typical fixes
- Check the sensor’s plug and wiring, and the boost hoses and clamps for splits and oil.
- Compare the sensor’s reading with the barometric pressure in live data, with the engine off.
- Have the boost control, the turbo’s vanes or wastegate and, for P2563, the vane position sensor checked.
- Replace the sensor if its reading is wrong, then clear the code and check the power on a test drive.
Questions
Can I drive with P0236?
Gently, and have it checked soon. Many engines cut the power when the boost can’t be measured or controlled, sometimes suddenly, and boost that isn’t controlled can damage the engine. Avoid full throttle and overtaking until it’s fixed.
Does P0236 mean the turbo is broken?
Not necessarily. The code is about the boost sensor’s reading. A faulty sensor, its wiring or a leaking hose are more likely, and easier to check, than the turbo itself.