P043E EVAP leak detection reference orifice low flow
What P043E means
Some cars check the EVAP system with a leak detection pump that first measures flow through a small reference orifice as a baseline. P043E means flow through that orifice was lower than expected, so the test cannot be completed correctly. The cause is usually a restriction rather than a leak.
P043E is a generic SAE J2012 code: it means the same on every make. The exact cause still depends on the car, so read the freeze-frame data before replacing parts.
At a glance
- Severity
- Medium
- Typical repair cost
- 80–600 €
- Workshop time
- 0.7–3 h
- Repair difficulty
- Medium
- DIY possible
- No
- Check engine light
- Yes
- Affects emissions test
- Yes
Parts and labour at an independent workshop in Europe. Main dealers charge more; the cause decides the bill, not the code.
Symptoms
- Check engine light on
- Car drives normally
- Possible difficulty refuelling if the vent is blocked
- Technical inspection failure for emissions
Common causes
- Blocked EVAP vent hose or vent filter (dirt, spider webs, water)
- Clogged reference orifice in the leak detection pump
- Faulty leak detection pump or module
- Restricted or kinked hose between canister and pump
- Saturated charcoal canister
Can I keep driving with P043E?
Yes, you can keep driving. Have it checked within one or two weeks.
What to check first
- Inspect the vent hose and filter near the canister for blockage
- Check the hoses between the canister and leak detection pump for kinks
- Run the EVAP leak test with a scan tool and check pump operation
- Replace the leak detection pump or module if the reference flow stays low
Related codes
- P043F EVAP leak detection reference orifice high flow
- P0440 Evaporative emission (EVAP) system malfunction
- P0441 EVAP system incorrect purge flow
- P0442 EVAP system small leak detected
- P0443 EVAP purge control valve A circuit
- P0446 EVAP vent control circuit
- P0449 EVAP vent valve control circuit/open
- P0431 Warm-up catalyst efficiency below threshold (bank 2)
Data: TORKO fault-code catalogue, built on OBDex (CC0-1.0) and reviewed against workshop practice. Informational only — it does not replace a diagnosis by a mechanic.
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