This test is to determine the effectiveness of the evaporative emission system. This system is to prevent gasoline vapor from passing to the atmosphere. You will find a vacuum line schematic under the hood. There is a vacuum line that goes from the intake manifold to the charcoal cannister (mounted on the L. F. Inner fender). Check that vacuum line for leaks, and check that the solenoid valve located in that line is actually opening and closing. With the engine off, it should be closed.
Next, check the line that goes from the charcoal cannister back to the fuel tank. Any bad spots in this line will cause a gasoline odor to be smelled under the car. If all of these lines are OK, then there is a leak at the fuel tank or line attachment.
Tuesday, February 24th, 2009 AT 6:55 PM