1994 Mercury Sable, 3.8, 79,000 MI : ROUGH START, SHAKING

MY MERCURY SABLE STARTS ROUGH IN THAT IT PUTTERS WHEN I FIRST START IT AND I HAVE TO GIVE IT SOME GAS BEFORE IT WILL RUN WELL.

ONCE I DO DRIVE, IT STILL PUTTERS FOR A FEW HUNDRED FEET, RUNS LESS THAN SMOOTH AND SHAKES SOMEWHAT, ESPECIALLY WHEN IT IDLES.

THE CAR SATOUTSIDE FOR 8 MONTHS, UNDRIVEN, , BEFORE I BOUGHT. WHEN I FIRST GOT IT, IT HAD A DEAD BATTERY AND A BROKEN MOTOR MOUNT. SO FAR, I'VE ALSO HAD TO HAVE A TIRE REPAIRED, REPLACE THE MUFFLER, AND THE SERPENTINE BELT.

I'VE HAD TWO MECHANICS LOOK AT IT (ONE WHO HAS WORKED ON MY CARS BEFORE), AND BOTH SAY THEY CAN'T FIND ANYTHING WRONG AND THAT IT'S BAD GAS, I'M JUST HEARING THINGS, OR IT'S JUST A BAD CAR. THIS IS NO COMFORT AND NONE OF THIS RESOLVES THE PROBLEM.

I HOPE YOU CAN HELP ME. THANK YOU.