If a car sits for about 3 monthes?

If my ford explorer (1999) with 107,000 miles on it sits for about 3 months. Then I start it up one day and travel 1200 miles how will it affect the car. Will it make it the 1200 miles and be alright?

After standing for 3 months, then before you start the car, you remove the spark Plugs and squirt some engine oil into the pistons. This will lubricate the Cylinders before the oil in the sump has a chance to oil the piston walls. Also, the rear brakes may be stuck on. So after replacing the Spark Plugs, release the handbrake, and see if the car moves forward without holding back.

Crystal ball time?

There's nothing that sitting for 3 months does that should serioulsy harm a car. The battery may go flat, or the tires may loose some pressure. So you check and fix those things before you leave.

Now something might randomly break on the trip, but that's no more likely than any other time.

Sitting for 3 months will just leave you with a dead battery. But once you charge that up, drive gently for the first few miles to get oil back into all the components. After about 5 mins of driving gently, you're good to go.

Pulling the plugs and squirting oil is Way overkill after a 3-month idle---3-yrs, yes.

If it sits for three months it probably will have bad gas In the tank. Treat the gas and mix it with good gas. Otherwise your fuel filter will go bad, the fuel pressure regulator will go bad too, and the injectors will gum up.

If it was OK when you parked it and you change the oil and check the fluid levels and tire pressure, your're all good.

Probably no problems at all. But I would check the fuids and tire presure before I left/

Before a trip like that you should have the vehicle looked over either way. And that kind of time sitting could cause issues with brakes.