EVAP System Leak Detected (Very Small Leak)
2000-2005 Chevrolet Impala 3.8L V6
Description
A very small leak has been detected in the EVAP system. These are the hardest EVAP leaks to find.
Symptoms
- Check Engine Light
- Very slight fuel smell possible
Common Causes
- Gas cap seal worn
- Micro-crack in EVAP hose
- O-ring deterioration
- Charcoal canister hairline crack
- Fuel tank seal degradation
Diagnostic Steps
- Check and replace gas cap first
- Smoke test EVAP system at low pressure
- Inspect all hose connections
- Check canister and all seals
- May need to pressurize fuel tank
Repair Notes
Replace gas cap first. If code returns, smoke test is essential. Very small leaks can be time-consuming to locate.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P0456 on Other Vehicles
Chevrolet Astro
1995-2005 4.3L V6 Vortec
Chevrolet Avalanche
2002-2006 5.3L V8 Vortec
Chevrolet Avalanche
2002-2006 8.1L V8 Vortec
Chevrolet Avalanche
2007-2013 5.3L V8 Vortec
Chevrolet Avalanche
2007-2013 6.0L V8 Vortec
Chevrolet Aveo
2012-2018 1.6L I4
Chevrolet Beat
2018-2021 1.2L I4
Chevrolet Beretta
1990-1996 2.2L I4
Common Questions
What does code P0456 mean on a 2000-2005 Chevrolet Impala?
P0456 stands for "EVAP System Leak Detected (Very Small Leak)". A very small leak has been detected in the EVAP system. These are the hardest EVAP leaks to find.
What are the symptoms of P0456 on a Chevrolet Impala?
Common symptoms of P0456 include: Check Engine Light, Very slight fuel smell possible.
What causes P0456 on a 2000-2005 Chevrolet Impala?
Common causes of P0456 include: Gas cap seal worn, Micro-crack in EVAP hose, O-ring deterioration, Charcoal canister hairline crack, Fuel tank seal degradation.