Home / DTC / P0455 — Missing fuel cap, Defective or damaged fuel cap, Distorted or damaged Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective Evaporative Vent Valve and or Evaporative Purge Valve, Defective or damaged fuel tank, Defective Fuel Tank Pressure Sensor

P0455 — Missing fuel cap, Defective or damaged fuel cap, Distorted or damaged Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective Evaporative Vent Valve and or Evaporative Purge Valve, Defective or damaged fuel tank, Defective Fuel Tank Pressure Sensor

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Code

P0455

AUDI P — Powertrain

Missing fuel cap, Defective or damaged fuel cap, Distorted or damaged Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective Evaporative Vent Valve and or Evaporative Purge Valve, Defective or damaged fuel tank, Defective Fuel Tank Pressure Sensor

Brand: AUDI
Views: UK: 45 EN: 53 RU: 73
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Missing or loose fuel filler cap
  • Defective or damaged fuel cap seal
  • Distorted or damaged fuel tank filler neck
  • Torn, cracked or disconnected EVAP hoses or fittings
  • Defective fuel tank sending unit gasket or seal
  • Split or damaged carbon (charcoal) canister

Symptoms

  • Malfunction Indicator Lamp (MIL/Check Engine) illuminated
  • Strong fuel odor around the vehicle or fuel filler area
  • Failed EVAP readiness or failed emissions test
  • No drivability symptoms in many cases (engine may run normally)

What to check

  • Read and record all stored codes and freeze-frame data with a scan tool
  • Visually inspect fuel cap for damage and confirm it is tightened/latches correctly
  • Inspect filler neck, tank area and EVAP hoses for cracks, disconnections or obvious damage
  • Check for fuel smell near filler, canister and hoses
  • Use a smoke machine or EVAP leak tester to locate a large leak quickly
  • Monitor EVAP-related live data (fuel tank pressure, purge/vent valve status) with a scan tool

Signal parameters

  • Fuel Tank Pressure / EVAP Pressure PID (kPa or inches H2O) — should hold pressure; large drop indicates gross leak
  • Fuel Tank Pressure Sensor voltage (typical reference ~0.1–4.9 V depending on pressure) — compare to expected at key reference points
  • Purge valve commanded state and actual response (ON/OFF or duty cycle)
  • Vent valve/vent solenoid commanded state and actual response (should close to allow pressurization during test)
  • EVAP system leak test result (smoke flow or pressure decay rate)

Diagnostic algorithm

  1. Confirm P0455 is current and note freeze frame/other EVAP codes
  2. Visually inspect and tighten the fuel cap; replace cap and clear codes if cap damaged or missing — re-test readiness and monitor for return
  3. Perform a visual inspection of the filler neck, tank area, EVAP hoses, clamps and connections for cracks, splits, or disconnections
  4. Use a calibrated smoke machine to pressurize the EVAP system and observe for escaping smoke at hoses, fittings, filler neck, canister and tank seams
  5. With a scan tool, command the vent and purge valves and verify they respond; inspect for a valve stuck open that prevents system sealing
  6. Monitor fuel tank pressure PID during a pressure or vacuum test; confirm the system holds pressure for the expected time
  7. If smoke/visual tests point to a component (hose, canister, valve, tank seam), replace the failed part and re-test the system
  8. If no physical leak is found, test/replace the fuel tank pressure sensor and check wiring/connectors; then clear codes and perform drive cycle to verify repair
  9. After repair, clear codes and perform drive cycle or readiness tests; re-scan to ensure P0455 does not return

Likely causes

  • Loose or missing fuel cap (first and easiest to check)
  • Cracked or disconnected EVAP hose or fitting
  • Failed vent or purge valve (stuck open)
  • Damaged carbon canister or tank leak
  • Faulty fuel tank pressure sensor or its wiring harness

Fault status

⚠️ Status
P0455 — EVAP Emission Control System Leak Detected (large leak). Inspect EVAP components, fuel cap, hoses and fuel tank pressure sensor.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

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Code

P0455

DODGE P — Powertrain

Large EVAP Leak

Brand: DODGE
Views: UK: 46 EN: 64 RU: 77
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Missing or loose fuel filler cap
  • Defective or damaged fuel cap seal
  • Distorted or damaged fuel tank filler neck
  • Torn, cracked or disconnected EVAP hoses or fittings
  • Defective fuel tank sending unit gasket or seal
  • Split or damaged carbon (charcoal) canister

Symptoms

  • Malfunction Indicator Lamp (MIL/Check Engine) illuminated
  • Strong fuel odor around the vehicle or fuel filler area
  • Failed EVAP readiness or failed emissions test
  • No drivability symptoms in many cases (engine may run normally)

What to check

  • Read and record all stored codes and freeze-frame data with a scan tool
  • Visually inspect fuel cap for damage and confirm it is tightened/latches correctly
  • Inspect filler neck, tank area and EVAP hoses for cracks, disconnections or obvious damage
  • Check for fuel smell near filler, canister and hoses
  • Use a smoke machine or EVAP leak tester to locate a large leak quickly
  • Monitor EVAP-related live data (fuel tank pressure, purge/vent valve status) with a scan tool

Signal parameters

  • Fuel Tank Pressure / EVAP Pressure PID (kPa or inches H2O) — should hold pressure; large drop indicates gross leak
  • Fuel Tank Pressure Sensor voltage (typical reference ~0.1–4.9 V depending on pressure) — compare to expected at key reference points
  • Purge valve commanded state and actual response (ON/OFF or duty cycle)
  • Vent valve/vent solenoid commanded state and actual response (should close to allow pressurization during test)
  • EVAP system leak test result (smoke flow or pressure decay rate)

Diagnostic algorithm

  1. Confirm P0455 is current and note freeze frame/other EVAP codes
  2. Visually inspect and tighten the fuel cap; replace cap and clear codes if cap damaged or missing — re-test readiness and monitor for return
  3. Perform a visual inspection of the filler neck, tank area, EVAP hoses, clamps and connections for cracks, splits, or disconnections
  4. Use a calibrated smoke machine to pressurize the EVAP system and observe for escaping smoke at hoses, fittings, filler neck, canister and tank seams
  5. With a scan tool, command the vent and purge valves and verify they respond; inspect for a valve stuck open that prevents system sealing
  6. Monitor fuel tank pressure PID during a pressure or vacuum test; confirm the system holds pressure for the expected time
  7. If smoke/visual tests point to a component (hose, canister, valve, tank seam), replace the failed part and re-test the system
  8. If no physical leak is found, test/replace the fuel tank pressure sensor and check wiring/connectors; then clear codes and perform drive cycle to verify repair
  9. After repair, clear codes and perform drive cycle or readiness tests; re-scan to ensure P0455 does not return

Likely causes

  • Loose or missing fuel cap (first and easiest to check)
  • Cracked or disconnected EVAP hose or fitting
  • Failed vent or purge valve (stuck open)
  • Damaged carbon canister or tank leak
  • Faulty fuel tank pressure sensor or its wiring harness

Fault status

⚠️ Status
P0455 — EVAP Emission Control System Leak Detected (large leak). Inspect EVAP components, fuel cap, hoses and fuel tank pressure sensor.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

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Code

P0455

Generic P — Powertrain

EVAP System Leak Detected - Large Leak

Brand: Generic
Views: UK: 45 EN: 59 RU: 87
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Missing or loose fuel filler cap
  • Defective or damaged fuel cap seal
  • Distorted or damaged fuel tank filler neck
  • Torn, cracked or disconnected EVAP hoses or fittings
  • Defective fuel tank sending unit gasket or seal
  • Split or damaged carbon (charcoal) canister

Symptoms

  • Malfunction Indicator Lamp (MIL/Check Engine) illuminated
  • Strong fuel odor around the vehicle or fuel filler area
  • Failed EVAP readiness or failed emissions test
  • No drivability symptoms in many cases (engine may run normally)

What to check

  • Read and record all stored codes and freeze-frame data with a scan tool
  • Visually inspect fuel cap for damage and confirm it is tightened/latches correctly
  • Inspect filler neck, tank area and EVAP hoses for cracks, disconnections or obvious damage
  • Check for fuel smell near filler, canister and hoses
  • Use a smoke machine or EVAP leak tester to locate a large leak quickly
  • Monitor EVAP-related live data (fuel tank pressure, purge/vent valve status) with a scan tool

Signal parameters

  • Fuel Tank Pressure / EVAP Pressure PID (kPa or inches H2O) — should hold pressure; large drop indicates gross leak
  • Fuel Tank Pressure Sensor voltage (typical reference ~0.1–4.9 V depending on pressure) — compare to expected at key reference points
  • Purge valve commanded state and actual response (ON/OFF or duty cycle)
  • Vent valve/vent solenoid commanded state and actual response (should close to allow pressurization during test)
  • EVAP system leak test result (smoke flow or pressure decay rate)

Diagnostic algorithm

  1. Confirm P0455 is current and note freeze frame/other EVAP codes
  2. Visually inspect and tighten the fuel cap; replace cap and clear codes if cap damaged or missing — re-test readiness and monitor for return
  3. Perform a visual inspection of the filler neck, tank area, EVAP hoses, clamps and connections for cracks, splits, or disconnections
  4. Use a calibrated smoke machine to pressurize the EVAP system and observe for escaping smoke at hoses, fittings, filler neck, canister and tank seams
  5. With a scan tool, command the vent and purge valves and verify they respond; inspect for a valve stuck open that prevents system sealing
  6. Monitor fuel tank pressure PID during a pressure or vacuum test; confirm the system holds pressure for the expected time
  7. If smoke/visual tests point to a component (hose, canister, valve, tank seam), replace the failed part and re-test the system
  8. If no physical leak is found, test/replace the fuel tank pressure sensor and check wiring/connectors; then clear codes and perform drive cycle to verify repair
  9. After repair, clear codes and perform drive cycle or readiness tests; re-scan to ensure P0455 does not return

Likely causes

  • Loose or missing fuel cap (first and easiest to check)
  • Cracked or disconnected EVAP hose or fitting
  • Failed vent or purge valve (stuck open)
  • Damaged carbon canister or tank leak
  • Faulty fuel tank pressure sensor or its wiring harness

Fault status

⚠️ Status
P0455 — EVAP Emission Control System Leak Detected (large leak). Inspect EVAP components, fuel cap, hoses and fuel tank pressure sensor.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

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Code

P0455

GWM P — Powertrain

- Significant leakage in the control system for the removal of fumes of fuel

Brand: GWM
Views: UK: 20 EN: 24 RU: 34
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Missing or loose fuel filler cap
  • Defective or damaged fuel cap seal
  • Distorted or damaged fuel tank filler neck
  • Torn, cracked or disconnected EVAP hoses or fittings
  • Defective fuel tank sending unit gasket or seal
  • Split or damaged carbon (charcoal) canister

Symptoms

  • Malfunction Indicator Lamp (MIL/Check Engine) illuminated
  • Strong fuel odor around the vehicle or fuel filler area
  • Failed EVAP readiness or failed emissions test
  • No drivability symptoms in many cases (engine may run normally)

What to check

  • Read and record all stored codes and freeze-frame data with a scan tool
  • Visually inspect fuel cap for damage and confirm it is tightened/latches correctly
  • Inspect filler neck, tank area and EVAP hoses for cracks, disconnections or obvious damage
  • Check for fuel smell near filler, canister and hoses
  • Use a smoke machine or EVAP leak tester to locate a large leak quickly
  • Monitor EVAP-related live data (fuel tank pressure, purge/vent valve status) with a scan tool

Signal parameters

  • Fuel Tank Pressure / EVAP Pressure PID (kPa or inches H2O) — should hold pressure; large drop indicates gross leak
  • Fuel Tank Pressure Sensor voltage (typical reference ~0.1–4.9 V depending on pressure) — compare to expected at key reference points
  • Purge valve commanded state and actual response (ON/OFF or duty cycle)
  • Vent valve/vent solenoid commanded state and actual response (should close to allow pressurization during test)
  • EVAP system leak test result (smoke flow or pressure decay rate)

Diagnostic algorithm

  1. Confirm P0455 is current and note freeze frame/other EVAP codes
  2. Visually inspect and tighten the fuel cap; replace cap and clear codes if cap damaged or missing — re-test readiness and monitor for return
  3. Perform a visual inspection of the filler neck, tank area, EVAP hoses, clamps and connections for cracks, splits, or disconnections
  4. Use a calibrated smoke machine to pressurize the EVAP system and observe for escaping smoke at hoses, fittings, filler neck, canister and tank seams
  5. With a scan tool, command the vent and purge valves and verify they respond; inspect for a valve stuck open that prevents system sealing
  6. Monitor fuel tank pressure PID during a pressure or vacuum test; confirm the system holds pressure for the expected time
  7. If smoke/visual tests point to a component (hose, canister, valve, tank seam), replace the failed part and re-test the system
  8. If no physical leak is found, test/replace the fuel tank pressure sensor and check wiring/connectors; then clear codes and perform drive cycle to verify repair
  9. After repair, clear codes and perform drive cycle or readiness tests; re-scan to ensure P0455 does not return

Likely causes

  • Loose or missing fuel cap (first and easiest to check)
  • Cracked or disconnected EVAP hose or fitting
  • Failed vent or purge valve (stuck open)
  • Damaged carbon canister or tank leak
  • Faulty fuel tank pressure sensor or its wiring harness

Fault status

⚠️ Status
P0455 — EVAP Emission Control System Leak Detected (large leak). Inspect EVAP components, fuel cap, hoses and fuel tank pressure sensor.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

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Code

P0455

HUMMER P — Powertrain

Evaporative Emission (EVAP) System Leak Detected

Brand: HUMMER
Views: UK: 25 EN: 30 RU: 40
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Missing or loose fuel filler cap
  • Defective or damaged fuel cap seal
  • Distorted or damaged fuel tank filler neck
  • Torn, cracked or disconnected EVAP hoses or fittings
  • Defective fuel tank sending unit gasket or seal
  • Split or damaged carbon (charcoal) canister

Symptoms

  • Malfunction Indicator Lamp (MIL/Check Engine) illuminated
  • Strong fuel odor around the vehicle or fuel filler area
  • Failed EVAP readiness or failed emissions test
  • No drivability symptoms in many cases (engine may run normally)

What to check

  • Read and record all stored codes and freeze-frame data with a scan tool
  • Visually inspect fuel cap for damage and confirm it is tightened/latches correctly
  • Inspect filler neck, tank area and EVAP hoses for cracks, disconnections or obvious damage
  • Check for fuel smell near filler, canister and hoses
  • Use a smoke machine or EVAP leak tester to locate a large leak quickly
  • Monitor EVAP-related live data (fuel tank pressure, purge/vent valve status) with a scan tool

Signal parameters

  • Fuel Tank Pressure / EVAP Pressure PID (kPa or inches H2O) — should hold pressure; large drop indicates gross leak
  • Fuel Tank Pressure Sensor voltage (typical reference ~0.1–4.9 V depending on pressure) — compare to expected at key reference points
  • Purge valve commanded state and actual response (ON/OFF or duty cycle)
  • Vent valve/vent solenoid commanded state and actual response (should close to allow pressurization during test)
  • EVAP system leak test result (smoke flow or pressure decay rate)

Diagnostic algorithm

  1. Confirm P0455 is current and note freeze frame/other EVAP codes
  2. Visually inspect and tighten the fuel cap; replace cap and clear codes if cap damaged or missing — re-test readiness and monitor for return
  3. Perform a visual inspection of the filler neck, tank area, EVAP hoses, clamps and connections for cracks, splits, or disconnections
  4. Use a calibrated smoke machine to pressurize the EVAP system and observe for escaping smoke at hoses, fittings, filler neck, canister and tank seams
  5. With a scan tool, command the vent and purge valves and verify they respond; inspect for a valve stuck open that prevents system sealing
  6. Monitor fuel tank pressure PID during a pressure or vacuum test; confirm the system holds pressure for the expected time
  7. If smoke/visual tests point to a component (hose, canister, valve, tank seam), replace the failed part and re-test the system
  8. If no physical leak is found, test/replace the fuel tank pressure sensor and check wiring/connectors; then clear codes and perform drive cycle to verify repair
  9. After repair, clear codes and perform drive cycle or readiness tests; re-scan to ensure P0455 does not return

Likely causes

  • Loose or missing fuel cap (first and easiest to check)
  • Cracked or disconnected EVAP hose or fitting
  • Failed vent or purge valve (stuck open)
  • Damaged carbon canister or tank leak
  • Faulty fuel tank pressure sensor or its wiring harness

Fault status

⚠️ Status
P0455 — EVAP Emission Control System Leak Detected (large leak). Inspect EVAP components, fuel cap, hoses and fuel tank pressure sensor.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

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Code

P0455

LAND ROVER P — Powertrain

Leak in the system of evaporative control detected (gross leakage)

Views: UK: 18 EN: 26 RU: 34
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Missing or loose fuel filler cap
  • Defective or damaged fuel cap seal
  • Distorted or damaged fuel tank filler neck
  • Torn, cracked or disconnected EVAP hoses or fittings
  • Defective fuel tank sending unit gasket or seal
  • Split or damaged carbon (charcoal) canister

Symptoms

  • Malfunction Indicator Lamp (MIL/Check Engine) illuminated
  • Strong fuel odor around the vehicle or fuel filler area
  • Failed EVAP readiness or failed emissions test
  • No drivability symptoms in many cases (engine may run normally)

What to check

  • Read and record all stored codes and freeze-frame data with a scan tool
  • Visually inspect fuel cap for damage and confirm it is tightened/latches correctly
  • Inspect filler neck, tank area and EVAP hoses for cracks, disconnections or obvious damage
  • Check for fuel smell near filler, canister and hoses
  • Use a smoke machine or EVAP leak tester to locate a large leak quickly
  • Monitor EVAP-related live data (fuel tank pressure, purge/vent valve status) with a scan tool

Signal parameters

  • Fuel Tank Pressure / EVAP Pressure PID (kPa or inches H2O) — should hold pressure; large drop indicates gross leak
  • Fuel Tank Pressure Sensor voltage (typical reference ~0.1–4.9 V depending on pressure) — compare to expected at key reference points
  • Purge valve commanded state and actual response (ON/OFF or duty cycle)
  • Vent valve/vent solenoid commanded state and actual response (should close to allow pressurization during test)
  • EVAP system leak test result (smoke flow or pressure decay rate)

Diagnostic algorithm

  1. Confirm P0455 is current and note freeze frame/other EVAP codes
  2. Visually inspect and tighten the fuel cap; replace cap and clear codes if cap damaged or missing — re-test readiness and monitor for return
  3. Perform a visual inspection of the filler neck, tank area, EVAP hoses, clamps and connections for cracks, splits, or disconnections
  4. Use a calibrated smoke machine to pressurize the EVAP system and observe for escaping smoke at hoses, fittings, filler neck, canister and tank seams
  5. With a scan tool, command the vent and purge valves and verify they respond; inspect for a valve stuck open that prevents system sealing
  6. Monitor fuel tank pressure PID during a pressure or vacuum test; confirm the system holds pressure for the expected time
  7. If smoke/visual tests point to a component (hose, canister, valve, tank seam), replace the failed part and re-test the system
  8. If no physical leak is found, test/replace the fuel tank pressure sensor and check wiring/connectors; then clear codes and perform drive cycle to verify repair
  9. After repair, clear codes and perform drive cycle or readiness tests; re-scan to ensure P0455 does not return

Likely causes

  • Loose or missing fuel cap (first and easiest to check)
  • Cracked or disconnected EVAP hose or fitting
  • Failed vent or purge valve (stuck open)
  • Damaged carbon canister or tank leak
  • Faulty fuel tank pressure sensor or its wiring harness

Fault status

⚠️ Status
P0455 — EVAP Emission Control System Leak Detected (large leak). Inspect EVAP components, fuel cap, hoses and fuel tank pressure sensor.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

Your experience will help others
+100 karma for a short comment :)
Send to email
Code

P0455

MITSUBISHI P — Powertrain

EVAP.emission(gross leak)

Views: UK: 24 EN: 33 RU: 41
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Missing or loose fuel filler cap
  • Defective or damaged fuel cap seal
  • Distorted or damaged fuel tank filler neck
  • Torn, cracked or disconnected EVAP hoses or fittings
  • Defective fuel tank sending unit gasket or seal
  • Split or damaged carbon (charcoal) canister

Symptoms

  • Malfunction Indicator Lamp (MIL/Check Engine) illuminated
  • Strong fuel odor around the vehicle or fuel filler area
  • Failed EVAP readiness or failed emissions test
  • No drivability symptoms in many cases (engine may run normally)

What to check

  • Read and record all stored codes and freeze-frame data with a scan tool
  • Visually inspect fuel cap for damage and confirm it is tightened/latches correctly
  • Inspect filler neck, tank area and EVAP hoses for cracks, disconnections or obvious damage
  • Check for fuel smell near filler, canister and hoses
  • Use a smoke machine or EVAP leak tester to locate a large leak quickly
  • Monitor EVAP-related live data (fuel tank pressure, purge/vent valve status) with a scan tool

Signal parameters

  • Fuel Tank Pressure / EVAP Pressure PID (kPa or inches H2O) — should hold pressure; large drop indicates gross leak
  • Fuel Tank Pressure Sensor voltage (typical reference ~0.1–4.9 V depending on pressure) — compare to expected at key reference points
  • Purge valve commanded state and actual response (ON/OFF or duty cycle)
  • Vent valve/vent solenoid commanded state and actual response (should close to allow pressurization during test)
  • EVAP system leak test result (smoke flow or pressure decay rate)

Diagnostic algorithm

  1. Confirm P0455 is current and note freeze frame/other EVAP codes
  2. Visually inspect and tighten the fuel cap; replace cap and clear codes if cap damaged or missing — re-test readiness and monitor for return
  3. Perform a visual inspection of the filler neck, tank area, EVAP hoses, clamps and connections for cracks, splits, or disconnections
  4. Use a calibrated smoke machine to pressurize the EVAP system and observe for escaping smoke at hoses, fittings, filler neck, canister and tank seams
  5. With a scan tool, command the vent and purge valves and verify they respond; inspect for a valve stuck open that prevents system sealing
  6. Monitor fuel tank pressure PID during a pressure or vacuum test; confirm the system holds pressure for the expected time
  7. If smoke/visual tests point to a component (hose, canister, valve, tank seam), replace the failed part and re-test the system
  8. If no physical leak is found, test/replace the fuel tank pressure sensor and check wiring/connectors; then clear codes and perform drive cycle to verify repair
  9. After repair, clear codes and perform drive cycle or readiness tests; re-scan to ensure P0455 does not return

Likely causes

  • Loose or missing fuel cap (first and easiest to check)
  • Cracked or disconnected EVAP hose or fitting
  • Failed vent or purge valve (stuck open)
  • Damaged carbon canister or tank leak
  • Faulty fuel tank pressure sensor or its wiring harness

Fault status

⚠️ Status
P0455 — EVAP Emission Control System Leak Detected (large leak). Inspect EVAP components, fuel cap, hoses and fuel tank pressure sensor.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

Your experience will help others
+100 karma for a short comment :)
Send to email