P0235 — Turbocharger/Supercharger Engine Overboost Condition
Drivable short-term, but fix now to avoid damage.
What P0235 means
This code means the engine computer detected that the turbocharger or supercharger is generating more boost pressure than the target, a condition called overboost. It's often caused by a stuck wastegate, a faulty boost control solenoid, or a leaking or disconnected vacuum line. Fixes typically involve repairing the wastegate, replacing the boost control solenoid, or fixing the vacuum and pressure lines that regulate boost.
Common symptoms
- Check engine light is on
- Reduced power or limp mode engages
- Surging or sudden bursts of acceleration
- Whistling or unusual turbo noises
- Poor fuel economy or rough running under boost
Common causes
- Stuck or sticking turbo wastegate
- Faulty boost control solenoid
- Leaking, cracked, or disconnected vacuum hose
- Failed boost pressure sensor sending wrong readings
- Binding or damaged variable-vane turbo mechanism
Typical repair cost
$150 – $1200
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0235 code?
You can usually drive a short distance, especially if the car is in limp mode, but you shouldn't drive it hard. Sustained overboost can damage the engine, so get to a shop without pushing the throttle.
How much does it cost to fix a P0235 code?
Repairs typically range from about $150 to $1,200. A vacuum hose or boost solenoid fix is on the lower end, while wastegate or turbo-related repairs can be much more.
Is a P0235 code serious?
Yes. Overboost puts extra stress on the engine and can cause real damage if ignored, which is why many cars cut power to protect themselves. Have it addressed promptly.
What causes a turbo to overboost?
Overboost usually happens when the wastegate that's supposed to bleed off excess pressure sticks shut, or when the boost control solenoid or vacuum lines fail. The turbo then keeps building more pressure than the engine is set up to handle.