My 1990 Brougham De Elegance keeps stalling out whenever put into anything but P or N. Lately the problem has only gotten worse and the car will just stall out after 30-45 seconds in P unless I'm giving it throttle the whole time. I just had the battery replaced with a brand new everstart and also had the oil changed, oil filter changed, and air filter. I'm very low on money and I can't afford to get the car towed to autozone for them to do a diagnostic. What is the best route to go.

Also, if I shut the car off, sometimes the motor will rumble and shake and make some noises for about 15-20 seconds before it settles down.

Sounds as if you have bad plugs or wires. When you was under the hood last did u touch any wires? Meaning bend to move out of the way? Sounds as if your car isnt truly running on all plugs.

I would say chck your plugs, wires and might even be your Cap