how do you check your coils

how do i check the coils on a vehicle or coil pack thanks

This is usually done with an ohmmeter by measuring the various resistance values of the coil, then comparing them against the factory specifications.

not sure if all are the same...my MSD coil just has a positive and negative connection. Hook the batter postive to the positive terminal on the coil, then hook a wire from the ground of the coil and have someone hold the sparkplug wire from the coil to the chassis or soemthing metal. When you connect the ground wire to the chassis (ground it out) The coil should produce one spark which you should be able to hear. Everytime you make and break the circuit, it makes a spark.

It's usually not recommended to fire the ignition outside of the engine, can in worst case cause damage to the ignition system.

Also note that powerful coils can overheat if they are connected to a powersource too long without discharges.

being completely eliminated from the electrical loop from the ignition, i do see how that is possible. You do want to be careful when performing such a task, as the spark is over 40,000 volts. But, as maybe i should have stated before, the ground and positive should be disconnected, and you use other wires to connect the coil independently to the batter and ground.

Another issue with that sort of a test is that the results are also dependant on the condition of the spark plugs and wires (more if it is a distributor ignition system).

being completely eliminated from the electrical loop from the ignition, i do see how that is possible. You do want to be careful when performing such a task, as the spark is over 40,000 volts. But, as maybe i should have stated before, the ground and positive should be disconnected, and you use other wires to connect the coil independently to the batter and ground.
Firing the coil off load should be avoided as it can cause cumulative damage by electrical breakdown.
This according to McLaren Electronic Systems.

This Is True Another Very Easy Way Without Having To Take Anything Off But Open The Hood Unless Under The Dash Is Run It Through The Computer And It Should Tell You Firing Sequences,order, Amount Of Spark Ingnition Retard And Amount Of Resistance And Ohms And Current Running Through The Ingnition System. Be Careful To Who You Take It To. I Suggest You Take It To A Certified Mechanic With An Obd-ii Computer .

Onboard diagnostics generation/level 2 computer

so the safest way to check them is by using the ohmetter and cheking for resistanse from each coil negative and positive