After you get your fueling issues corrected, IF you still have the shaking problem. When the car is fully warmed up and shaking , Do a compression test. Much easier than pulling a valve cover. (if you own or can borrow a compression tester) A tight valve will drop compression readings on that cylinder. If you find a low cylinder, that is the valve cover to remove and check valve adjustment. (Of course if one is tight you must check them all) If you find a tight one and your lucky the valve won't be burnt and your car will be back to 100% (for an 18 year old car)