In an unusual announcement today, the National Highway Traffic Safety Administration (NHTSA) voiced concerns that millions of Ford vehicles previously recalled for a faulty cruise control system may have not been repaired, despite FoMoCo's notification efforts.

The safety agency noted that Ford Motor Company "has been diligent in contacting owners of the affected vehicles, including sending re-notification letters to owners in many cases."

According to the feds, since 1999, approximately 17.5 million Ford vehicles have been involved in the recalls because of the faulty cruise control disconnect switch, which can overheat and burn, potentially causing a fire long after the engine has been turned off.

"As more of the affected vehicles enter the used car market, the agency is concerned that most used car buyers don't know whether the used vehicles they purchased were ever returned to dealers for the needed repairs," the NHTSA said in a statement.

The agency said it advising owners of the affected Ford models to watch for potential warning signs of an imminent fire, including: a cruise control system that can't be activated or stops working; brake lights that stop working; low brake fluid; ABS and brake warning lights that are illuminated on the dashboard; or the inability to get a vehicle out of park.

Concerned owners can visit Ford's dedicated recall page and enter their Vehicle Identification Number (VIN) to see if their particular model has been recalled for the problem and if the repair has been made.

Here's the complete list of affected vehicles with the defective cruise control system:

• 1992-2003 E Series (all including Econolines)
  
• 1992-1998 Crown Victoria/Grand Marquis/Town Car
  
• 1993-2003 F Series (150-550)
  
• 2003-2004 Lightning
  
• 2002-2003 Blackwood
  
• 1993-1997 F Series (>8500GVW Diesel)
  
• 1999-2003 F Series (>8500GVW Diesel)
  
• 1993-1995 Taurus SHO
  
• 1993-1998 Mark VIII
  
• 1993-1996 Bronco
  
• 1994-2002 F53 Motorhome
  
• 1994 Mercury Capri
  
• 1995-2003 Ranger
  
• 1995-2002 Explorer
  
• 2001-2002 Explorer Sport & Sport Trac
  
• 1995-2002 Mountaineer
  
• 1995-2003 Windstar
  
• 1997-2002 Expedition
  
• 1998-2002 Navigator
  
• 1998-2002 Mazda-B-Series
  
• 2000-2003 Excursion