The Ford Taurus Vacuum Leak Symptomsby Steven Symes
Normally a Ford Taurus runs smoothly, but a vacuum leak can cause problems with the operation of the engine. A vacuum leak is any opening in the engine block that allows air to come into the engine. The introduction of an uncontrolled source of air will cause several symptoms to manifest in a Taurus.
The computer on a Ford Taurus regulates how much air comes into the engine via the throttle body. If there is a vacuum leak, air is entering the engine through another source, which will cause the car to idle at a higher RPM than normal.
More Idle Problems
Idling will not be normal on a Taurus with a vacuum leak. The engine will run roughly while the car is waiting at stop lights or in the driveway. The engine's RPMs will fluctuate as the car idles, going up and down repeatedly. If the vacuum leak is severe enough, the Taurus can even stall out while idling, requiring the driver to depress the accelerator slightly to keep the car running during idling.
A Taurus with a vacuum leak will not accelerate normally. The car will hesitate or sputter when the accelerator is depressed. The car may even stall out completely during acceleration, which puts the driver and occupants in a dangerous situation.