Sorry for the lengthy silence, but I have been traveling.

The seat problem did, in fact, turn out to be a seat cable. The replacement was relatively inexpensive but involved a bit of labor.

Be careful when the new cable is installed that the seat is level at each side. In my instance the bad cable had caused the right side to lift without the left side. When the new cable was installed the unevenness was not fully corrected and will need to be adjusted.

Hope this helps.

__________________
David

2010 E350 Coupe / 1K miles
2007 ML350 / 18k miles (Gone, gone, gone!)
1995 E320 Wagon / 170k miles
2008 Audi A6 4.2 / 12k miles
2006 Mitsubishi Endeavor / 25k miles