I ran across this EMP study today so I thought I would post it here in the Library for reference. In short, the study found that most car's and trucks would not be affected by a solar flare or low level EMP detonation above a country.
Many vehicles tested in the study were moderately affected in that disconnecting then reconnecting the cables from the battery seemed to do the trick.
Out of 30 some vehicles used in the study, only one failed to restart and was hauled off to a garage to be repaired.
It's a long read so grab a cup of joe before you start.
http://www.futurescience.com/emp/vehicles.html
