Mobile operating is highly popular, but some effort may be required to obtain a reasonably noise free installation.  We not only have installation tips and interference cures, but have obtained policy statements from the auto manufacturers.

• Automotive Electric Motor and Fuel Pump Noise
• K0BG's Thoughts on Mobile Interference
• Automotive Interference Problems: What the Manufacturers Say
• Lab Notes -- Mobile Installations and Electromagnetic Compatibility
  QST March 1995, pp. 74-75

• These pages describe techniques to eliminate alternator whine. As these articles point out, a bad diode can make the whine much worse:
  • http://www.termpro.com/articles/noise.html
  • http://www.avweb.com/news/maint/182896-1.html
• Ford Motor Company EMC Online
  Contains much information including Mobile Radio Installation Guidelines
• Ford Explorer Radio Frequency Interference
• W8LMF Mobile Installation In 2005 Toyota Prius - Contains information and graphics for an Amateur Radio installation in a modern hybrid vehicle