EngineLightCodes
Powertrain code

P023E Manifold Absolute Pressure - Turbocharger/Supercharger Boost Sensor B Correlation

Severity
Fix soon
Typical repair cost
$40–$280
Do it yourself
Possible, easy
Shop time
0.5–2 hours

Boost sensor B is a second boost pressure sensor, for a second turbo or bank on parallel twin-turbo engines or a second stage on two-stage systems.

How the engine computer detects it

No manufacturer using sensor B codes was found – GM, Ford and Saab, even on two-stage and twin-turbo engines, use a single boost sensor; the description follows CARB and the documented sensor A codes. P023E is the counterpart of P023D: manifold pressure is compared with boost sensor B, and with the engine stopped both must read ambient pressure. Saab sets the sensor A version at a difference of more than 12 kPa (1.7 psi); a deviation beyond the manufacturer's limit sets this code.

Written from public technical sources and not yet checked by a mechanic. How we write these pages

Symptoms

  • Check engine light on
  • Possibly limited power
  • Otherwise unremarkable

Common causes

  1. Boost sensor B or manifold sensor drifting Most likely
  2. Contact resistance at sensor B's connector or wire Possible
  3. Pressure port blocked Less likely

How to diagnose P023E

  1. Read every stored code with an OBD-II scanner. If misfire or fuel trim codes are there too, fix those first: they often cause this one.
  2. Inspect the parts involved: manifold absolute pressure sensor, boost pressure sensor b, sensor wiring.
  3. Work through the causes above from most to least likely, cheapest checks first.
  4. Clear the code and drive a full drive cycle to confirm the repair held.

Reading the code

P
Powertrain
0
Generic (SAE) code
2
Fuel and air metering (injector circuit)
3E
Specific fault

Questions drivers ask

Can I drive with code P023E?

Drive gently and only as far as you need to. The engine computer may limit power to protect the engine, so avoid highways and heavy traffic until it's fixed. If the check engine light starts flashing, pull over.

Will my car pass an emissions inspection with P023E?

Probably not in states that test vehicles with an OBD-II scan: an emissions-related code that keeps the check engine light on is usually an automatic fail. Rules differ by state and county, so check yours.

Can I fix P023E myself?

Often yes, with an OBD-II scanner and basic tools. Difficulty: easy. Start with the cheapest checks before replacing expensive parts.

This page is general information, not a substitute for a professional diagnosis. Repair costs are rough estimates for parts and labor and vary by vehicle and region.