What causes an engine to idle fast?
In modern vehicles, engine idle speed is most often controlled by the idle air control (IAC) motor. This can be impacted by bad fuses in many different electronic systems in your car. Next, your high idling could be caused by a computer malfunction. And a bad alternator can also cause fast idling in your engine.
What is fast engine idle?
The car has a central computer that is set up to run the engine at about 1,200 r.p.m. when it is cold, which is a lot faster than you are probably used to. Some GM cars are set up to idle at 1,600 r.p.m. when cold.
What does it mean when your car Idles too fast?
But if the accelerated idle persists even after the engine is fully warmed up, it probably indicates a genuine problem. Troubleshooting Fast Idle Problems The first step is to determine if there are any diagnostic trouble codes stored in the PCM (powertrain control module).
How does an engine Stop Start system work?
SISS would have manipulated the alternator load to stop all four pistons exactly halfway through their stroke. To restart, the cylinder in its compression stroke would get a small squirt of fuel that, when burned, would spin the internals backward just enough to produce compression in the neighboring cylinder.
How does Mazda’s smart Idle Stop system work?
Mazda tried to complicate things in 2008 when it teased engine geeks with its theoretical Smart Idle Stop System (SISS), which attempted the operation without relying on the starter motor. SISS would have manipulated the alternator load to stop all four pistons exactly halfway through their stroke.
How do I adjust the idle speed of my car?
If so, adjusting the idle speed will also save gas and improve engine performance. To make the adjustment, locate the idle adjustment screw on the carburetor — it’s usually marked “I” — and while the engine is running, turn the screw counterclockwise.