I have a 2000 Quad Cab Sport with a 3.9L V-6.
135,000 Miles.

Last November the Upper Coolant Hose to the Intake Manifold failed and I replaced it.
Ever since then I've noticed a slight vibration in the steering wheel during idle at Stop Lights that wasn't there before, and my mileage dropped.
I was getting 21 mpg overall and now I'm getting 14 mpg.

Since this started, I replaced the Plugs, Wires, Cap and Rotor.
I also back-flushed the coolant/heater and replaced the thermostat.

Could a Vacuum Sensor have gotten wet and gone bad?
Should I test the Vacuum Hoses?
Not sure where to go from here.

Thanks
Rich