Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
EGR System: Description
The exhaust gas recirculation (EGR) system is used to help control formation of NOx emissions. By recycling a limited amount of exhaust gas back to the intake system, combustion temperatures are lowered, which helps keep NOx emissions down.
The system consists of EGR valve, EGR pipe, thermostatic valve, control valve orifice and vacuum outlet.
The EGR system operates differently for non-turbo and turbo, but the thermostatic valve, which deactivates the EGR system below 112°F (43°C), is controlled by coolant temperature in both systems.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.