EGR Throttle Control Circuit A High
What it means
P2142 means the PCM detected an abnormally high voltage on the "A" EGR throttle control circuit. This circuit operates the throttle/valve that meters recirculated exhaust gas back into the intake for emissions control. Because it's an emissions fault, the car usually still drives normally, though a misbehaving EGR system can cause pinging under load. The most likely causes are wiring or connector faults, a failed EGR throttle actuator, or carbon build-up.
Can I keep driving? Drivable — it's an emissions/EGR fault, but you may notice pinging or hesitation under load, so fix it before long or hard driving.
Common symptoms
What you'll notice
- Check-engine light on
- Pinging or knock under load or at higher speeds
- Hesitation or a slight drop in performance
- Often no obvious symptom other than the light
Common causes
Most likely first
- Open or short in the EGR throttle control circuit wiringLikely
- Poor or corroded connector at the EGR throttle valve/actuatorCommon
- Faulty EGR throttle valve or its control solenoidCommon
- Carbon build-up restricting the EGR throttle/passagesLess often
- Faulty PCM driver for the EGR throttle circuit (least likely)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check for related EGR codes.
- Inspect the EGR throttle control wiring and connector for opens, shorts, and corrosion — a 'circuit high' fault usually points to a wiring or connector problem.
- Clean the EGR throttle, valve, and passages if carbon build-up is present.
- Test the EGR throttle actuator/solenoid and its command with a scan tool.
- Replace the EGR throttle valve if it fails testing; clear and re-test.
FAQ
Quick answers
Is it safe to drive with P2142?+
Can I just clear P2142?+
Related codes
Often seen with P2142
Read & clear P2142 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.