1993 mercury tracer shakes and sputters and is slow to accelerate you find you can get it going better at lower rpms so you shift early it also smells like it is flooding new fuel filter plugs O2?

It could be a sticky/dirty injector, a bad air filter, sticking EGR valve or any of a number of problems. If you suspect flooding, run some injector cleaner through the next tank of fuel. Also, check the air filter and make sure the intake is free of obstructions. If it runs well at low RPM's, it could just mean that it's not getting enough air.