OBD-II code · Powertrain (generic)
P00E4 Exhaust Heat Exchanger Exhaust Bypass Valve A Stuck Closed
The exhaust heat exchanger bypass valve A is stuck closed. Risk of overheating because exhaust always passes through the heat exchanger.
Is it safe to drive with P00E4?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyValve stuck closed by carbon
- Less likelyCarbon or debris buildup preventing free movement
- Less likelyComponent wear with age - mechanical play
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 2–6 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Exhaust Bypass Valve A, Heat Exchanger
Related codes
- P00E1Charge Air Cooler Coolant Temperature Sensor A Circuit High
- P00E2Charge Air Cooler Coolant Temperature Sensor A Intermittent/Erratic
- P00E3Exhaust Heat Exchanger Exhaust Bypass Valve A Stuck Open
- P00E5Intake Air Temperature/Fuel Temperature Correlation
- P00E6Intake Air Pressure Measurement System - Multiple Sensor Correlation Bank 2
- P00E7Intake Air Temperature Measurement System - Multiple Sensor Correlation Bank 2
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.