OBD-II code · Powertrain (generic, extended)
P24A5 EGR Cooler Bypass Control Stuck Open Bank 1
The EGR cooler bypass valve on bank 1 is mechanically stuck in the open (bypassing) position - EGR always bypasses the cooler, gas reaches the intake hotter than designed.
Is it safe to drive with P24A5?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyValve stuck open
- Less likelyCarbon or debris buildup preventing free movement
- Less likelyComponent wear with age - mechanical play
Symptoms
- Check engine light on
- Pinging or knocking under load
- Power loss and hesitation
- Possible rough idle
- Failed emissions inspection (NOx)
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 1–3 h
- Emissions test
- Likely to fail
- Parts involved
- Egr Cooler Bypass Valve B1
Related codes
- P24A6EGR Cooler Bypass Control Stuck Open Bank 2
- P24A2Particulate Filter Regeneration Incomplete Bank 1
- P24A3Particulate Filter Restriction Soot Accumulation Bank 2
- P24A4Particulate Filter Restriction Soot Accumulation Too High Bank 1
- P24A7EGR Cooler Coolant Pump Control Circuit Open
- P24A8EGR Cooler Coolant Pump Performance Stuck Off
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.