Fuel injectors spray a fine mist of fuel into the engine. Over time, deposits build up on the tips and the spray pattern goes uneven. The engine gets less out of each litre, and you may feel it as a rough idle or a stumble when you pull away.
The throttle body is the valve that lets air into the engine when you press the gas. Oily vapour from inside the engine leaves a layer of carbon on it and through the air intake. On many cars that's enough to make the idle shaky or the engine slow to respond.
We scan for codes first, then clean the injectors. Next we take off the intake duct and clean the throttle body and the air passages behind it. Some cars need an idle relearn afterwards so the engine settles at the right speed, and we do that before the car leaves.
Why it matters
Better fuel economy
Dirty injectors spray fuel unevenly, so the engine burns more to make the same power. Clean injectors help it get more from each tank.
A smoother idle
Carbon around the throttle plate changes how much air gets past at idle. The engine computer can only make up for so much. After that, the idle starts to hunt or shake.
City driving builds deposits
Short trips and stop-and-go traffic don't let the engine run hot long enough to burn deposits off. Commuting in traffic and short winter errands are exactly that kind of driving.
Signs it's time
- Fuel economy has slowly dropped
- Idle that hunts up and down or feels shaky
- Hesitation when you press the gas
- Engine stalls when you come to a stop
- Slow or uneven response from a stop
What's included
- Code scan before we start
- Fuel injectors cleaned
- Air intake duct removed and checked
- Throttle body and throttle plate cleaned of carbon
- Engine air filter checked
- Idle relearn on cars that need one
- Test drive to check idle and response
How often
When symptoms show up
Most manufacturers don't list a set interval. Many drivers have it done when they notice a rough idle or falling fuel economy, or alongside a tune-up on a higher-kilometre car.
