Engine
What is an EGR Valve?
A small valve that recycles exhaust gas to reduce emissions.
Simplified animation — not to scale.
In plain English
EGR stands for Exhaust Gas Recirculation. The valve sends a small amount of exhaust gas back into the engine to lower the combustion temperature and cut harmful nitrogen-oxide emissions.
A simple analogy
"Like opening a window to let cooler air into a hot oven — keeps temperatures (and pollution) down."
How it works
The engine's computer opens the valve at certain speeds, mixing cooled exhaust with fresh air going into the cylinders. Less oxygen means a cooler burn and cleaner emissions.
Signs of trouble
- ⚠Rough idle or engine stalling
- ⚠Loss of power, especially on motorways
- ⚠Engine management light (EML)
- ⚠Failed MOT emissions test
Rough UK cost
£200 – £500 fitted
Always get a written quote. Prices vary by car, region, and parts brand.
Heads up: Carautonomy is for general guidance only. If your car is showing warning lights or behaving oddly, get it looked at by a qualified mechanic.