P0046

Turbocharger/Supercharger Boost Control A Circuit Range/Performance

Turbo / boost control Generic OBD-II High

What it means

P0046 means the boost control circuit for the turbo or supercharger isn't performing within its expected range — actual boost doesn't match what the ECM commands. It usually points to the boost control solenoid, the wastegate and its plumbing, or the boost pressure sensor. The engine keeps running but often drops into a reduced-power limp mode to avoid over- or under-boosting.

High

Can I keep driving? Driveable, but the engine may drop into reduced-power limp mode to protect against over- or under-boost; repair before hard driving.

Real-world scan data

Seen in

438

scans in the past year

Found in

0.1%

of scans

0.1%

of scans that found faults

Appears alongside · share of P0046 scans

P0113in 19.6% of scans

P0101in 16.9% of scans

P2599in 13.9% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Lack of power or noticeable turbo lag
Reduced-power (limp) mode
Poor fuel economy

Common causes

Most likely first

Faulty boost control solenoid / wastegate control valveLikely
Wiring or connector fault in the boost control circuitCommon
Stuck or leaking wastegate or vacuum/boost actuator linesCommon
Faulty boost pressure sensor giving a mismatched readingLess often
Failed ECM (least likely)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame data and compare commanded boost to actual boost on a scan tool.
Inspect boost control vacuum/pressure lines and the wastegate actuator for leaks or sticking.
Check the boost control solenoid connector, wiring and resistance against spec.
Verify the boost pressure sensor reads accurately; replace the failed component. Clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0046?+

Briefly, but the engine may limit power and boost control is unreliable, so avoid sustained hard acceleration until it's fixed.

Can I just clear P0046?+

It returns once the ECM sees boost not matching the command; repair the solenoid, plumbing or sensor first.

Read & clear P0046 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX