20 06 ford lariat running rough no lights on
what do you mean no lights on
A little more info please. But from what you said, check the alternator. If shot the entire vehicle is operating off the power from the battery. But that is only a guess from what was asked.
such as check engine light
How many miles are on the truck? The 2006 F150 has the coil on plug (COP) design and should be changed around 100k miles. This would cause it to run rough without triggering any lights. Jegs has "store" brand coils that run way cheaper than what you will find at a typical autoparts.
Plugs would also need to be replaced
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