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P043FMinorEmissions

P043F: Evaporative Emission System Leak Detection Reference Orifice High Flow

2 vehicles · 1 makes · $150-$500 repair

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Most Reported On

2006-2010Toyota RAV42011-2020Toyota SiennaL +4

P043F is an OBD-II diagnostic trouble code meaning “Evaporative Emission System Leak Detection Reference Orifice High Flow.” Generic OBD-II code. The engine control module runs a calibration check through a small precision reference orifice (roughly 0.02 in) in the EVAP leak detection pump/module, and measured flow through that orifice was higher than the expected specification. Because the orifice is the yardstick the module uses to size real leaks, a high-flow reading means the EVAP leak test can no longer be trusted. The driver usually notices nothing beyond a check engine light, but the vehicle will fail an emissions test. It frequently sets alongside P043E, P2401, P2402 or P2419, which point at the same leak detection pump module on the charcoal canister. This code is most commonly reported on 2006-2010 Toyota RAV4, and 2011-2020 Toyota Sienna (L, LE, SE, XLE, Limited), with repair costs ranging from $150 to $500.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (2)
  • Related Codes
  • FAQ
  • Sources (4)
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Common Causes

1Damaged, enlarged, or cracked reference orifice inside the EVAP leak detection pump/module
2Leak in the hose or line between the leak detection module and the canister or fuel tank
3Failed EVAP leak detection pump assembly
4Loose, missing, or non-sealing fuel cap / filler neck seal allowing extra flow
5Electrical fault in the leak detection pump circuit skewing the measurement
6Rarely, a PCM/ECM software calibration or module fault

Typical Repair Cost

$150 - $500

Based on 2 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

This is a powertrain code, so a basic OBD-II reader can read it. These read P043F.

Reads P codes$20–$40

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple code reader for engine (P) codes on many compatible OBD-II vehicles. It does not support every vehicle or hybrid/EV application, and it does NOT read body, chassis or network codes; confirm exact-vehicle compatibility before buying.

  • ✓Read & clear engine (P) codes
  • ✓View freeze frame data
  • ✓I/M readiness status
  • ✓No batteries or app needed
Check Price on Amazon
Reads P codes$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth scanner with a companion app that reads beyond the engine module — ABS, SRS and transmission — plus manufacturer-specific codes on many vehicles.

  • ✓Enhanced diagnostics (ABS, SRS, transmission)
  • ✓Repair Reports with verified fixes
  • ✓Smog check readiness
  • ✓Free app (iOS & Android)
Check Price on Amazon
Reads P codes$180–$230

LAUNCH CRP123X V3.0 Elite OBD-II Scanner

by LAUNCH

Handheld scanner covering the four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • ✓Engine, transmission, ABS, SRS diagnostics
  • ✓Live data stream & graphing
  • ✓AutoVIN for vehicle identification
  • ✓Free lifetime updates via Wi-Fi
Check Price on Amazon
Reads P codes$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level tablet with all-system coverage and bi-directional control, so you can command a module rather than only read it.

  • ✓All-system diagnostics (25+ modules)
  • ✓Bi-directional control & active tests
  • ✓Oil reset, EPB, BMS, TPMS, injector coding
  • ✓7-inch touchscreen with Android OS
Check Price on Amazon

What you can do yourself, and what needs a shop

Reading the code, clearing it, and watching whether it returns is a driveway job with the right scanner. These steps are not:

  • •Module programming or software updates — needs the manufacturer software or a J2534 pass-through with a paid subscription.
  • •Replacing a control module — most are VIN-programmed and immobilizer-registered, so a new one does nothing until it is coded to your car.
  • •Airbag/SRS component work — a stored fault can deploy a live device.

If the vehicle is still under warranty, check for an open recall or technical service bulletin before buying anything — the repair may already be covered.

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (2)

Toyota P043F page →
RAV4Moderate

2006-2010 RAV4 Liquid Fuel in EVAP System - T-SB-0046-10

2006-2010
SiennaMinor

EVAP System Leak-Detection / Vapor Canister Fault (Check Engine Light, Hard Refueling)

2011-2020$150-$500

Related Codes (8)

P0430Catalyst System Efficiency Below Threshold (Bank 2)P0431Warm Up Catalyst Efficiency Below Threshold (Bank 2)P0432Main Catalyst Efficiency Below Threshold (Bank 2)P0433Heated Catalyst Efficiency Below Threshold (Bank 2)01447EVAP System (VAG)P0030HO2S Heater Control Circuit (Bank 1 Sensor 1)P0031HO2S Heater Control Circuit Low (Bank 1 Sensor 1)P0032HO2S Heater Control Circuit High (Bank 1 Sensor 1)

FAQ

What does P043F mean?

P043F stands for "Evaporative Emission System Leak Detection Reference Orifice High Flow." Generic OBD-II code. The engine control module runs a calibration check through a small precision reference orifice (roughly 0.02 in) in the EVAP leak detection pump/module, and measured flow through that orifice was higher than the expected specification. Because the orifice is the yardstick the module uses to size real leaks, a high-flow reading means the EVAP leak test can no longer be trusted. The driver usually notices nothing beyond a check engine light, but the vehicle will fail an emissions test. It frequently sets alongside P043E, P2401, P2402 or P2419, which point at the same leak detection pump module on the charcoal canister.

What are the most common causes of P043F?

The most common causes of P043F are: Damaged, enlarged, or cracked reference orifice inside the EVAP leak detection pump/module, Leak in the hose or line between the leak detection module and the canister or fuel tank, Failed EVAP leak detection pump assembly, Loose, missing, or non-sealing fuel cap / filler neck seal allowing extra flow, Electrical fault in the leak detection pump circuit skewing the measurement, Rarely, a PCM/ECM software calibration or module fault. The specific cause varies by vehicle.

How much does it cost to fix P043F?

Repair costs for P043F range from $150 to $500, depending on the vehicle and root cause.

Which vehicles are affected by P043F?

Au7o has documented P043F across 2 vehicle models from 1 manufacturers: Toyota.

Sources (4)

  • TSBToyota T-SB-0046-10: MIL On - Fuel in EVAP System
  • ForumSiennaChat — CEL Codes P043E P043F P2401 P2402 P2419
  • ForumSiennaChat — EVAP codes P0441, P0455 and pending P0446
  • articleGo-Parts — P0455 on 2011-2020 Toyota Sienna: EVAP Large Leak causes and fixes
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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