95 SL2 with occasional drivability trouble

I have a 1995 SL2 5spd with 142000 miles. For the past year when I drive the car up a steep hill with a left hand bend, by the time I get to the top of the hill and it levels out, the car is running poorly. It seems to be missing or is flooded. If I shift to neutral the car idles very rough and at about 300-500 rpm. Sometimes the car will stall after being shifted to neutal. It usually fires right back up and runs fine after that. If I continue to drive normally, I can feel reduced performance and lack of smoothnes, and these symptoms will go away eventually. Based on other driveability problems the car had and by looking at previous threads, I replace the ECTS and connector. The car runs great now, but I still have this after up-hill trouble. But the car does not do this at every steep hill. Could the throttle position sensor be bad? Maybe after being under load, the sensor thinks that the throttle is still open wide and the computer is sending too much fuel after the load is reduced and the hill levels off.

I appreciate any help. Thanks, and take care.

Update on old post:

This turned out to be a faulty EGR. Once I got the pintel to move on its full range of motion, this problem stopped.