New User 2002 Grand Marquis

Hello, I am an owner of a 2002 Grand Marquis. It has been a great car so far and entered our family from a friend who only drove it to the grocery store and church. It has been treated fairly well at the dealership by the older woman who sold it to us.

Recently some issues have arisen since the car reached just over 130k miles. I just had the ball joints and idler arm replaced because the car was eating tires pretty quickly. Now it drives like new again and is very smooth. The other issue that just popped up (and left me seeking deeper help) is a hesitation/misfire that occurs just after starting the car and driving up hills or accelerating. The car has also died once or twice in the last few months, always after starting.

There is also an unrelated (assumed) oil leak, every few thousand miles I have to add a quart or so. The car doesn't seem to burn oil though, and my local mechanic says it is an issue with the oil filter adapter or something of that nature.

Either way, thank you anyone for any help, I have purchased another fuel filter that I have yet to install and also considered looking into the throttle body/positioning sensor to see what that does.

At that age, it's possible the intake manifold is gone or going unless it was replaced recently. Look at the intake manifold and see if there is a Ford or Dorman symbol on the front of it.
Check the plugs to see if there is any coolant in around the spark plug, check the coils to see if the boots are worn, torn or broken. The rubber boot on the bottom of the coil can be replaced on its own if the boot on the coils looks like junk.
A few things to look at for oil leak are the valve cover gaskets(a pain to replace) and the oil filter adapter gasket. The filter adapter is the metal part bolted to the block that the filter screws on to, there is a gasket between the adapter and the block, often a good place to start. If you can get in there yourself, do it at the next oil change and check the pressure sender and clean the adapter while it's off. There are 2 pressure ports on the filter adapter, make sure they are sealed well(one has the oil pressure sender in it, one has a plug in it that is not used by the car).

Thanks, will check into that. Now I have another issue... The temperature gauge will not move, nothing. The check engine light has come on now too. I ran my Fix'd app and got a code P0125, warned me that continued driving could do severe damage. Really confused, this car is very important to our job/life.