I have noticed power loss at highway speeds look down at the gauges and notice that the message center says 'Failsafe mode'. The engine either quits or goes to a rough idle. To clear the message and restore engine performance I have to pull over put the transmission in park, shut off the engine, wait a minute or two and restart. This happens a few times a year over the past few years and has resulted in power steering loss and power brake loss while driving on the interstate at 60-70 mph. I have brought it to the Ford place and they stated that they could not replicate. It has been doing this since I bought the truck new. It now has 110k miles.
Engine periodically goes into Failsafe mode. on 2006 Ford F-150
by DanMc in Sulphur, LA on March 08, 2012
1 answer 1 comment
ANSWER by globalhelper , March 08, 2012
HAVE YOU HAD ANY CODES READ ON THE TRK?
COMMENT by Elwood Jarman , December 13, 2012
I had the same problem with my truck ('06 F150 5.4 Triton) and turned out to be the throttle body. Found a new/used on ebay cheap and replaced it. No more problems.