5.7 Vortec intermittent long crank --> crank no start, backfires, clunking

[99xcss4]

unplug the coil wire from either the cap or the coil and see if the spark jumps

 

[slow_c1500]

unplug the coil wire from either the cap or the coil and see if the spark jumps

What do you mean jumps? So I unplug the coil wire and see if a spark comes out of it?

 

[99xcss4]

see if a spark comes out of it?

yes you should be able to see it or hear it

 

[slow_c1500]

yes you should be able to see it or hear it

Sry for the dumb questions but this is while someone else is cranking the engine right? And what will it tell me if I do/don’t get a spark?

 

[99xcss4]

Sry for the dumb questions but this is while someone else is cranking the engine right? And what will it tell me if I do/don’t get a spark?

yes it will help you check for spark and yes some one watches it and some one cranks it another thing you can do is take a spark plug out plug it in to the plug wire and ground it out and crank on it and be careful it is very easy to get shocked

 

[slow_c1500]

yes it will help you check for spark and yes some one watches it and some one cranks it another thing you can do is take a spark plug out plug it in to the plug wire and ground it out and crank on it and be careful it is very easy to get shocked

I’ll try the coil method, should I also unplug the electrical connection for the coil and the ignition module? I heard it can be hard on them to crank with distributor wires unplugged.

 

[docstoy]

Don't hold on to wire or you will have sore arm . It will knock the sh_ _ out of you !!!

 

[slow_c1500]

Don't hold on to wire or you will have sore arm . It will knock the sh_ _ out of you !!!

I’ll just have it held in place under the trans fluid lock tab. Unless this is dumb?

 

[99xcss4]

I’ll try the coil method, should I also unplug the electrical connection for the coil and the ignition module? I heard it can be hard on them to crank with distributor wires unplugged.

no leave them pluged in or you will get no spark if you are getting spark right now

 

[99xcss4]

I’ll just have it held in place under the trans fluid lock tab. Unless this is dumb?

that might work you can hold on to it with a pliers but make shore that the handles are insolated or it will get you like said in another post