2000 corolla sluggish when accelerating, fine at higher RPMs

Replace the #2 coil. Second one starting on the passenger side.

-There is couple things cause that. Possibly:
-Spark plug too dirty, pack w/carbon, oil.
-Broken plug wire.
-Bad injector.
-dirty air flow sensor.

Good luck

Mai

the converter is what is restricting power from engine. causes of a bad converter are: decreased engine power, indicated by low rpms on the tach. hesitating or bucking during acceleration, the car will loose power going up a hill. if engine runs hotter then usual and coolant is up to par, it may indicate a bad converter. also black smoke from tail pipe is another indication of a bad converter. good- day!!

had same problem on 74crewcab the vacumn line was tee d into another giving low vacumn . when it did reach sufficent pressure the trans would shift but the engine rpm was very hjgh and result was it slammed the trans in gear. Inspect your vacumn hose from modulator to the intake manifold/carb itcould be leaking or some one may have rerouted by accident.it must have a vacum draw equal to manifold pressure to shift in time with the actual rpms of the engine hope this helps...that it shifts at all makes me thinnk the modulator valve is working --just the vacumn line(s) arenot draw full manifold pressure

I hope I'm wrong but I think your torque converter is failing. Sorry, Gary

coolant temperature sensor could be faulty, making fuel mixture too lean. will hesitate and feel flat until warm.

This IAC valve runs only when your foot is off the gas pedal. Mainly to keep the engine from stalling and keeping it at a safe RPM. If it is running bad under 2000RPM, more than likely its the IAC valve or a vacuum leak. Clean or replace the IAC valve....Hopefully this helps!!

goto walmart and get wynn's signature engine tuneup(8$) and put in your engine and run for 100 kms then have a oil change see the difference.

Sounds to me like it could be a Mass Airflow Sensor issue. Or Air fuel mixture problem. Is the harness to the MAF and Trottle control sensors hooked up right? These are just simple solutions that may work. Check all of your fuses as well. One could be blown causeing you DLC not to operate. DLC =DATA LINK CONNECTOR. Find the fuse... read the code.... solve them problem! GOOD LUCK! hope this helps.

try changing your fuel filter