Exhaust Pressure Control Valve
A butterfly in the exhaust that deliberately restricts flow. Two different systems use one: on commercial diesels it is an exhaust brake providing retardation on descents, and on many modern diesels it is a warm-up aid, since restricting the exhaust raises engine load and exhaust temperature and brings the after-treatment up to working temperature far sooner in cold weather. Soot and corrosion seize the spindle, and a valve stuck closed restricts the exhaust exactly as a blocked filter would.
Also known as: exhaust brake, exhaust throttle, back pressure valve, exhaust flap, epc valve
Referenced by 56 codes
Codes involving this component (56)
- P22D3 Turbocharger Turbine Inlet Valve Stuck Closed High
- P0475 Exhaust Pressure Control Valve A Moderate
- P0476 Exhaust Pressure Control Valve A Range/Performance Moderate
- P2169 Exhaust Pressure Regulator Vent Solenoid Control Circuit/Open Moderate
- P2170 Exhaust Pressure Regulator Vent Solenoid Control Circuit Low Moderate
- P2171 Exhaust Pressure Regulator Vent Solenoid Control Circuit High Moderate
- P0477 Exhaust Pressure Control Valve A Low Low
- P0478 Exhaust Pressure Control Valve A High Low
- P0479 Exhaust Pressure Control Valve A Intermittent Low
- P047F Exhaust Pressure Control Valve A Stuck Open
- P048A Exhaust Pressure Control Valve A Stuck Closed
- P048B Exhaust Pressure Control Valve A Position Sensor/Switch Circuit
- P048C Exhaust Pressure Control Valve A Position Sensor/Switch Circuit Range/Performance
- P048D Exhaust Pressure Control Valve A Position Sensor/Switch Circuit Low
- P048E Exhaust Pressure Control Valve A Position Sensor/Switch Circuit High
- P048F Exhaust Pressure Control Valve A Position Sensor/Switch Circuit Intermittent/Erratic
- P049F Exhaust Pressure Control Valve B
- P04A0 Exhaust Pressure Control Valve B Range/Performance
- P04A1 Exhaust Pressure Control Valve B Low
- P04A2 Exhaust Pressure Control Valve B High
- P04A3 Exhaust Pressure Control Valve B Intermittent
- P04A4 Exhaust Pressure Control Valve B Stuck Open
- P04A5 Exhaust Pressure Control Valve B Stuck Closed
- P04A6 Exhaust Pressure Control Valve B Position Sensor/Switch Circuit
- P04A7 Exhaust Pressure Control Valve B Position Sensor/Switch Circuit Range/Performance
Other components in Exhaust and Emissions
- Oxygen Sensor 326
- EGR Valve 150
- Catalytic Converter 142
- NOx Sensor 118
- Reductant Injector 107
- Exhaust Gas Temperature Sensor 95
- Reductant Tank 95
- Diesel Particulate Filter 76
- SCR Catalyst 65
- EGR Cooler 62
- Exhaust Gas Differential Pressure Sensor 58
- Fuel Tank Pressure Sensor 58
- Reductant Heater 55
- Reductant Pump 51
- EVAP Vent Valve 43
- Exhaust Aftertreatment Fuel Injector 42
- Charcoal Canister 33
- EGR Position Sensor 32
- Secondary Air Injection Pump 32
- Reductant Temperature Sensor 29
- EVAP Leak Detection Pump 29
- EVAP Purge Valve 27
- Particulate Matter Sensor 24
- Reductant Control Module 24
- Reductant Level Sensor 23
- Secondary Air Switching Valve 22
- EGR Temperature Sensor 21
- Secondary Air Check Valve 21
- Catalyst Heater 20
- Catalyst Temperature Sensor 20
- Fuel Filler Cap 18
- EGR Cooler Bypass Valve 16
- Reductant Quality Sensor 16
- Exhaust Back Pressure Sensor 15
- Purge Flow Sensor 13
- Direct Ozone Reduction Catalyst 13
- EGR Vacuum Solenoid 9
- Fuel Vapour Temperature Sensor 5
- Fuel Additive Control Module 4
- Fuel Additive Tank 4
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