Shifts hard when taking off and passing,will stall going up a hill then **** and take off

try briefly lifting your foot off the pedal, then punching it to get it to downshift.

I have seen many pass though my shop, these are some what known for this ! There's a 95% chance it is your TPS, throttle positions sensor, now the other 5% has also been there Crankshaft Sensor and IAC, are you doing you doing the work yourself ? If you are, it would help if you get a repair manual for your car. Because then you can follow the test for each of these, you would also need a multi meter to test with. On a scale of 1~5 with 5 being the hardest, I would say it's a 2.What you need the repair book for is the voltage to test for on each of these sensors.

you don't say if its petrol or diesel you could try changing fuel filters d ifficult siarting and running problems are usually fuel or electrical but try filters first

sounds pretty normal. what speed do you try out the passing gear? anything above 35-45 mph and it will feel like neutral. Passing gear is actually only 1st gear. When you press down the pedal, it forces the transmisson to shift into low gear.

Any engine light? Can you hear the fuel pump run for a couple seconds when you turn the key to ON?

A/T
The modern A/T has 4shift methods.
Foot (passing) called detent TV kick down cable.
the shift lever.
the Vacuum modulator (load, = hills)
and tail shaft RPM (speed)
so seems like the MOD on the A/T is bad.

If tranny is manual shift you may have a bearing and or bad gear. Try changing tranny fluid. Check manual for correct fluid may use tranny fluid rather than gear oil. I recommend using Royal Purple fluid or gear oil. This very expensive but will slicken up the shifting and extend bearing and gear life.

Your shifting to early! and try down shifting when you go up a hill.

Bad gas, bad sensor - take to auto parts store to read codes. Plugged cat.

hi if its just second to thrid then the clutch is slipping on thrid gear look at the boxes oil level is important but look at the colour is it red and tranperant as this is ok if its brown its a sign of the clutches slipping i would try a stall test on thrid gear first and if its ok second gear [manually] see is the engine stalls at the correct rpm if you thinkabout it imagine you are in thrid gear in a manuual box and suddenly drop into second it would be hard shifting it could also be a faulty thrid gear solenoid yates210456