depends on the type and model car. If it's got a carburettor, the mixture screw needs to be turned out a touch. If it's fuel injected, different kettle of fish, off to the mechanic
Look for a vacuum leak.
whiteish
The lienholder is under no obligation to pay for repairs - that's on you, as the lessee.
yes they can do this they just put another lean holder on the car same thing with a house
How to fix bank 1to lean on a 3100 v6
If a car dealership has a lean on your car and you have not made the required payments they may repossess your car.
Look for a blown fuse.
fix my car
If you are getting a Lean code then it is probably being caused by the intake plennum gaskets. This is a common problem on the Windstar. The fix is relatively easy.
Give engine more fuel
The year, make, model and engine info would help but, first you need to determine the cause before you can fix it.
You need to start by having it checked for codes. Then you will know what to diagnose/fix.