P0475 Code: Exhaust Pressure Control Valve A Malfunction
🟠 Moderate severity · drivable
Drivable, but the valve may stick and cause rough running or poor cold-weather performance; fix it soon.
What P0475 means
The exhaust pressure control valve, sometimes called the exhaust backpressure valve, adjusts backpressure in the exhaust to help the engine warm up and run cleanly. This code means the engine computer sees the valve or its control circuit working incorrectly. It is most common on diesel trucks and older turbo diesel engines.
Symptoms
- Check engine light is on
- Rough idle or stalling
- Hard starting in cold weather
- Loss of power or excessive exhaust smoke
Common causes
- most common: Valve stuck open or closed from carbon buildup
- common: Faulty valve actuator or solenoid
- common: Damaged wiring or vacuum lines to the valve
- less common: Faulty valve position sensor
- rare: Faulty engine computer
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Clean the valve and free it from carbon buildup | Yes | $50–150 |
| Replace the exhaust pressure control valve | Yes | $150–400 |
| Repair wiring or vacuum lines to the valve | Mechanic | $50–200 |
Frequently asked questions
Can I drive with a P0475 code?
Yes, usually. The engine will run, but it may idle rough or be hard to start in cold weather until the valve is fixed.
What does the exhaust pressure control valve do?
It builds up exhaust backpressure to help the engine warm up faster and run more cleanly, especially in cold weather.
How much does it cost to fix a P0475?
Cleaning the valve runs $50–$150. Replacing it typically costs $150–$400 including parts and labor.
Related codes
P0476
P0476 Code: Exhaust Pressure Control Valve A Range/Performance
P0477P0477 Code: Exhaust Pressure Control Valve A Low
P0478P0478 Code: Exhaust Pressure Control Valve A High
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.