P0456low severityPowertrain
EVAP System Leak Detected (Very Small Leak)
on 1997 Buick Century 3.1L V6 · FWD
What this code means
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.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1