P0242 — Turbocharger/Supercharger Boost Sensor B Circuit High

What Does P0242 Mean?

P0242 is a diagnostic trouble code indicating: Turbocharger/Supercharger Boost Sensor B Circuit High. This code relates to the fuel injection system. It has been reported in NHTSA complaints across 1 different vehicle models.

Symptoms of P0242

⚠️ Engine misfires

Common Causes

🔍 Failed or deteriorated catalytic converter

Real Owner Reports

From NHTSA complaint database — actual owner descriptions.

"TL* THE CONTACT OWNS A 2017 KIA SOUL. THE CONTACT STATED THAT THE ENGINE VIBRATED, ABNORMALLY, MISFIRED WHILE IDLING DUE TO A LOSS OF COMPRESSION AND COMBUSTION. THE CONTACT PERFORMED A DIAGNOSTIC TEST ON THE VEHICLE AND RETRIEVED TROUBLE CODE: P0242 (CATALYST LOW EFFICIENCY BELOW EFFICIENCY). THE V"
— Kia Soul owner, 10/14/2020

Source: NHTSA Complaints Database

Most Reported Vehicles for P0242

Based on NHTSA owner complaint data.

#	Vehicle	Reports
1	KIA SOUL

Frequently Asked Questions

Can I drive with this code?

It depends on the severity. If the vehicle runs normally, short trips are usually OK. If you notice performance issues, drivability problems, or warning lights beyond the check engine light, get it checked soon.

Will this code clear itself?

Some codes clear automatically after the underlying issue is fixed and several drive cycles pass. But the root cause must be addressed first.

How do I find the exact cause?

A code alone doesn't pinpoint the failed part. You need a diagnostic scan ($50-150 at most shops) that reads freeze frame data and live sensor readings to identify the specific component.

What To Do Next

Possible Fixes

🔧 Have the code scanned with a professional-grade scanner to read freeze frame data
🔧 If DIY repair isn't feasible, get a diagnostic from a trusted mechanic ($50-150)

1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

P0242: Turbocharger/Supercharger Boost Sensor B Circuit High