Q: What is normal idle for a 2005 Ford focus?

Hi There, Generally, the warm up high idle will last for less than a minute or so depending on the outside ambient temperature, however once the temperature sensor reaches the normal operating temperature (usually between 190-200 degrees F). This will also depend on the type of thermostat installed in the vehicle. Assuming it is the stock 180 degree thermostat, you should be fine. When the engine is first started anytime it is not at normal operating temperature the RPM may rise to around 1,250 or so for a few seconds until it idles down. It should settle in at around 750-800 RPM’s consistently. If this is not the case you may have something else wrong such as a faulty or dirty idle air control valve. The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This valve is controlled by the vehicle’s computer and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. This is also an important function when starting the motor as it allows the motor to run and idle on it’s own once the motor fires. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed while adjusting the air/fuel ratio constantly to allow this to happen smoothly.