Exhaust Heat Exchanger Exhaust Bypass Valve A Stuck Open
The exhaust heat exchanger bypass valve A is stuck open. Engine warms up too slowly because exhaust does not heat the heat exchanger.
Affected components
- Exhaust bypass valve a
- Heat exchanger
Common causes
- High likelihood: Valve stuck open by carbon
- Low likelihood: Carbon or debris buildup preventing free movement
- Low likelihood: Component wear with age - mechanical play
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.