97 LIncoln TC Signature slow to start after parked overnight


Junior Member
97 TC has been running perfect since I got a new fuel pump in March 1994, until now so here is the problem. After sitting for a day overnight, when I turn ignition, she starts but such low idle it almost stalls or like today even DOES stall, but then on next try, she starts up nice and normal. Then I drive, go shopping for a few hours and she starts right up and runs perfect to take me home.

I have replaced the battery and it seemed that might be the problem bc she started up nice and steady for several months after that, but now the prob is there again. I checked the Gen/Alternator on start-up and it is instant with 13-14 amps steady while car is running. Air filter checked and seems pretty clean.

Spark plugs are about 10 years old Autolite Platinum AP104, from when I purchased the car. However I only replaced the easy 5. The last 3 were too difficult to access under the air intake and I have no idea how old they were to years ago. I only drive a few hundred miles per year. Could it be related to spark plugs?
I know she's getting gas bc I can hear the pump spin just before I click the starter motor. Fuel pressure regulator was replaced during the 1994 fuel pump replacement. There was some water in the fuel and I thought that was causing it, but now there is no water coming out my tailpipe. It has been raining pretty heavy though.

Any clues on how I should procede to solve this puzzle would be greatly appreciated. Thanks in advance