P043E

EVAP System Leak Detection Reference Orifice Low Flow

Q: Is it safe to drive with P043E?

Yes. It's an evaporative-emissions self-test fault and does not affect how the car runs or starts. Get it fixed so the EVAP monitor can pass, especially before an emissions test.

Q: Can I just clear P043E?

You can, but it returns after the next EVAP self-test if the reference orifice or leak-detection pump is still faulty. Fix the cause first.

EVAP (emissions) Generic OBD-II Medium

What it means

P043E is set when the evaporative-emissions leak-detection system measures less airflow than expected through its calibrated reference orifice during a self-test. That orifice provides the baseline the system compares against to check for fuel-vapor leaks, so low flow usually points to a blocked orifice or a weak leak-detection pump rather than anything that affects driving.

Medium

Can I keep driving? Yes — this is an emissions self-test fault, not a running problem; the car drives normally, but the EVAP monitor won't pass until it's fixed.

Real-world scan data

Seen in

106

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Appears alongside · share of P043E scans

P043Fin 95.3% of scans

P2401in 91.5% of scans

P2402in 90.6% 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
No noticeable change in how the car drives
May fail an emissions/readiness test
Occasionally a faint fuel smell if paired with a real EVAP leak

Common causes

Most likely first

Blocked or contaminated reference orifice in the leak-detection assemblyLikely
Faulty leak-detection pump or module that draws air through the orificeCommon
Restricted or pinched EVAP hoses feeding the reference checkCommon
Wiring or connector fault at the leak-detection pump/moduleLess often
ECM control or calibration issue (least common)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame data and confirm no companion large-leak codes are stored first.
Locate the EVAP leak-detection pump/module and inspect the reference orifice for dirt, debris, or blockage.
Check the pump's electrical connector and wiring for corrosion or damage.
Test the leak-detection pump operation per the service procedure; replace the pump/module if the orifice or motor is faulty.
Clear the code and run the EVAP monitor drive cycle to confirm the repair.

FAQ

Quick answers

Is it safe to drive with P043E?+

Yes. It's an evaporative-emissions self-test fault and does not affect how the car runs or starts. Get it fixed so the EVAP monitor can pass, especially before an emissions test.

Can I just clear P043E?+

You can, but it returns after the next EVAP self-test if the reference orifice or leak-detection pump is still faulty. Fix the cause first.

Read & clear P043E 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