I have a 1990 chevy 1500 and I can't get any spark at the the plug wires changed coil from a truck I know works what else can I look for to be bad? the truck was running fine then started to sputter then just died and wont restart

If cap and rotor are good, check there is a continuous symmetrical signal from the ignition pickup coil (inside distributor).

you need to isolate which cylinder it is first may help.
while running use insulated pliers to pull each plug wire off plug or cap separately, you will hear idle change/drop when a good cylinder is pulled. it will not change when not firing cylinder is pulled. now u got the cylinder and can double check plug, wire connections there. see if that wire sparks on a ground or plug to check spark and eliminate that issue. if you get a zap you need a better insulated pliers, but you know that wire is good. Remember the 3 things needed on all engines- Spark, Fuel, Air. oh yes and Compression. if you have spark, then have cylinder compression tested 120-150psi is still good. 80psi sucks and you have bad rings or valves., fuel cleaner may help in that situation, rare fix, but cheaper than a new engine.

My 97 was doing this, I too put a lot of money before figuring out that it was a bad coil and coil wire. Works great now. Do you have the 4.3L

intake manifold gasket may be bad,if the coils were bad you would get no spark and no fire i doubt its your plugs

Have you tried reversing the wire's on the coil ?

change out your distributor cap and rotor button

Change the spark plugs,they are worn out.

Probably a bad ignition coil.

Check for spark at a plug first. If none then its either the coil or ignition module. The module is located under the coil.

change coil pickup which is in the bottom of the distrubuter