Truck wont start. battery test good.truck cranks over,but drags down after a couple of tries,has new starter and spark plugs, truck has good fire from coil but weak fire to the plugs could it be a moduale to the distributor? kk

No can't be PATS . PATS on your vehicle disables the starter . Pull a spark plug wire an check for spark , do fuel pressure testing etc...

Hi Able:
"Crank" to me means turn over.
"Fire" means actually try to run.
If it won't crank and you have a new battery and starter, I'd be checking the terminal connections, wires, cround connection, and solenoid. If all of those are good then we need to start checking the engine condition. Recently running or sitting for 5 years and full of rust?
Reply as a comment to this post for conversation.

the computer fires the injectors and the spark plugs. does the check engine lite illuminate and go thru boot up with ignition key in on position.

Is the fuel good or is the fuel pressure good?
How did you check for spark - are you certain it's firing the plug?
Why was the starter replaced?
What is the condition of the spark plugs?
Did you have a check engine light?

how did you make your test.spark plug wire test is made with special tools call HEI spark tester.and injector fuel pressure test.and wire to injector anoid light

Does the engine spin over and not start? Or turn the key and nothing happens?
New spark plugs and wires won't have anything to do with the starter and battery keeping the engine from spinning when you turn the key.
Need more specific explanation. Thanks,
Scott

Now it's time to become the gearhead in you and get this critter moving. The engine needs fuel, compression, and ignition (spark) to run. You must have heard the steady whuff, whuff, whuff of the cylinders pushing air out the sparkplug holes when you cranked it over with the plugs out, right? That was a good test of compression, if nothing else. Now look down the carburetor throat (with air cleaner removed) and operate the throttle with your hand. Does gas squirt down when you open the throttle plates. If it does, you know the engine is getting gas. The next thing is to check your ignition system-start at the spark plug and check for spark.-your '76 is heavenly simple compared to later models-but a good place to learn the basics. Still, I'd recommend buying a Haynes or Chilton repair manual for your truck. It can lead you step-by-step through any procedure you want to try, including the very problem you are having. .
Good luck.

Check all the battery and starter cables,particularly the earth cables off the battery.Also check the battery clamps.Check the earthing between the engine and chassis.if this is bad you can get this type of problem.

Narrow the problem down to a spark or fuel problem by spraying starter fluid into the intake. If the car starts for a few seconds, then you know there is a fuel delivery problem (fuel pump or injectors not firing). If it doesn't start for a few seconds then you know there is an ignition problem. In that case, the CKP or crankshaft position sensor circuit may not be functioning correctly.

Good luck on this diagnosis.

If it over heated, could have bad head gasket's, fill radiator with water, crank engine with radiator cap off, if water is push out of radiator while cranking, bad head gaskets', also remove spark plug's, crank engine if any water, bad head gasket, also when spark plug's removed, check for any water on them.If there is any water on plug's, bad head gasket, also could try doing a cylinder compression test, if bad compression, head gasket, no compression, wont start that way.