Truck when going up hill will studder.

I would suspect the injector. Since it is only one fuel injector and you have replaced the filter and fuel pump it is evident that you are getting fuel to the one injector. The problem is you are not getting it to go into the intake. The injector has to fire when the computer instructs it to. If the computer never receives a signal from the timing cam sensor or crank sensor if equipped the fuel will never enter into the intake. I would look at the cam and crank sensor then only after you pour fuel into the single injector to see if will start. If it starts for a brief moment and stop the timing and sensors are okay it is an issue with the injector

Did you change fuel filter?

When you changed your fuel pump, did you also change the filter?
Also, I had 4 pumps go out in 1 year on a truck I had. It was a crappy pump. Remember you get what you pat for.. Got the name brand and didn't have any more problems.. Also, look for a loose or pinched wire, had that happen too.
Good Luck!

Check your fuel pressure it should be 38-46 with key on engine off. If not within these specs replace pump.

WHAT YEAR IS THIS TRUCK.

one of the things your car is famous for is bad fuel pumps ... if you frequently drive on a nearly empty tank then suspect that fuel pump .. they have a plastic impeller that depends on a continuous flow of fuel to keep cool .. if you are low on gas then it might capture some air as you go around corners or up a hill .. when that happens the impeller overheats and then you have problems until its replaced ..(not an easy job) ... you can have the fuel pump tested for voume and pressure .. if you never let the car get low on gas then that may not be the problem .. yoiu should also check or change the fuel filter ..

Look for vacuum leaks. There are tons of hoses, replace dried and cracked ones....

The trans shift issue that you describe seems that the trans is being told to hold back the shift, there is a unit at the end of the vacuum tube, AT the trans, called a modulator. They have a rubber diaphram inside that fails and then trans fluid gets sucked into the engine, via this vac. hose. Pull it off and see if any trans fluid comes out...Should be ZERO.

Also, your vehicle must have regular trans service, especially you must change the FILTER. Disk material eventually clogs the filter, then trans fails really fast.

You may consider having a quick lube shop do the trans service, they use a machine that pumps new fluid in while unit is running, totally flushing converter, cooler,and lines...but DO replace the filter.

To be fair, the service suggestion has nothing to do with yoru complaint, necessarily...

I have the same exact problem that just started immediately AFTER I got a tranny service where they changed the Trans Fluid, Trans Filter, Fuel Filter. Took it back and they say nothing is wrong with it. Took it to the dealer thinking I could get some REAL answers... they just told me to replace spark plugs, wiring & coil, for $900. Only studders when quickly accelerating above 40mph. I've check other forums, they say to clean the Mass Air Flow sensor. Haven't tried it yet. This seems the easiest before replacing spark plugs. Any other suggestions anyone?? Please.....

it will purge itself when you go to start it.The injectors when they open. If you have fuel pressure.

Sounds like your not getting enough fuel from a bad fuel pump. As the pump heats up it stops sending the proper PSI of fuel from the pump to your engine. As it cools down it gets better but quickly returns once the pump heats back up. The only real solution is replacing the pump and fuel filter.
Make sure in the future to keep at least a half a tank of gas in it as the gas cools the pump.


Hope this helps..

Joe