Vehicle starts real hard but when it starts it runs great ( new plugs , cleaned out jets , found 1 bad coil and replaced ,--possible valve issue )

Check the exhaust is not blocked,replace spark plugs,check leads and spark is good,check compression.

have the tps checked possible dirty or bad connection in the sweep it's sealed so can't be cleaned.

2 things. come to mind.
i check the distributor advance works to spec with my timing light (strobe)
if that is ok, its a carb issue.

carbs fail for many reasons, (mostly gummed up inside)
we clean them. that fixes them. (with a kit)
I only have this for symptoms, and is not good.
MAJOR HESITATION AND STALLING OCCURS
does the engine have full power up any hill wide open throttle
is the Hesitation only a short time then catches up.
The carb (not stated P/N or brand) has jets, the if gummed up
will cause lean running.
so will any power valve jet.
ever tune it up. new spark pats, rotor all the way to spark plugs.
bad spark , loves to fail under load, that is its , magic.
carb>

1. low float bowl levels.
2. low fuel pressure causing above,
3. bad float valve , sticks closed and starts bowl of fuel, causing #1
4. Gummed up jets.
5. Gummed up emulsion tubes in carb body.
6. Choke stuck on, causing flooding,
7. Choke dead causing hard starts . (stuck open)
8. power valve clogged.
9. Highspeed accelerator pump bad, causing only sight hesitation.

my guess? based on 1 word "stall" its #1 to 3 or 6.
black spark plug tips would be #6

or if black sparks, the float valve is stuck open flooding engine and stalling.

we can go for days on carbs. but will not.

you need to take the heads off of the engine and have them re-built and cleaned ,,you have serious valve issues ...also before you do anything ..you may also have ignition coils or bad distributor and plugs as well as plug wires

look for vacuum leaks anywhere ..check under cap/coil for wear/dirt on ignition parts replace if dirty/blackened or wet..pull a plug and look for blackened tips or carbon bildup..replace plugs if dirty..is the truck carburerated or tbi..clean with stp carb and tbi cleaner..it will remove built up varnish and gunk in/on the throttle plate and jets..also some filters have a backpressure valve in them to prevent vapor lock in older vehicles that had this issue..if you can blow thru it should work ok..if not needs replaced with type that doent have the valve in it.(has arrow that shows flow direction)..good luck repost findings

If it starts up after sitting for a few minutes, (like 2 or 3) it could have a plugged fuel filter or the gas tank strainer built into the fuel valve could be plugged too. Drain the gastank anyway and change the gas with fresh. can't hurt. If it takes 15-30 minutes or after the bike cools some I would look at an ignition coil. Check to see if it has spark next time it quits.

Hi, run a number drill through the main jet. Even though you have carby cleaned it a thin layer of residue will remain on the walls of the jet. The problem you have is a lean misfire. Regards Phil.

How old are the spark plugs and wires. GM vehicles are great runners until something goes wrong with the typical spark or fuel delivery issues. Wires or fouled plugs may not set off the computer, it will just run crappy.

check and clean ur egr valve possible carboned up -clean valve with carb cleaner and check valve movement

Possible faulty coil pack. u evidently have no spark when cold