97 Buick Lesabre Ltd dragging/hesitanting/stalling

97 Buick Lesabre Ltd w 78890 original miles. Started hestitant/dragging going up inclines and when cruisin along at 55 and above but could accelerate thru. No codes. Got a suggestion to replace MAF and MAP sensors. I did that and now the car is stalling 15 times but once I am on the interstate she runs smooth. Oh, and previously before I replace MAF and MAP I disconnected them and car ran smooth but had code with check engine lite. Other suggestions have been it is the fuel pump, fuel pressure sensor, EGR, crank shaft sensor, fuel filter, CAT Convertor. What is going on with my car??????

Welcome to AF!

You are right at the tune-up interval. Don't believe OEM claims of 100k mile tune-ups, they just don't hold up in real world driving. Since your issue is right at torque converter lock up when the engine is under load, it could be in need of plugs, wires, PCV valve and fuel filter. Try the normal maintenance stuff before replacing expen$ive parts that may not be needed.

already did tune up with new plugs, haven't replace fuel filter & pvc valve; replaced serpentine belt and alternator.

IF that didn't cure it, then you probably have a TCC solenoid sticking and not unlocking the torque converter fast enough.

unplugged throttle sensor in order for the computer to set a new set point and the ruff idol stoped. It may be the carbon bulid up after all. what do you think