GM-GMC: 93, splicing tool, wire insulation

Question
I have a 93 GMC Sierra 1500 that was running and suddenly died. The car turns over but there is no spark at the spark plugs or the distributor. I have tried the fuses and they seem in working order. I do not know how to test power to the distributor. Sugguestions?

Answer
You should consider buying a service manual for you truck, they can be your best friend when it comes to problems like this, they have every test you will ever need to perform in them.  Here is the test for an ignition module

Use a wiring diagram for the year model of your vehicle. Locate the terminals running into and out of the ignition module. Placement of the module varies from model to model so check the service manual for the year model of your vehicle for the exact location.

Step 2Turn the ignition on and use your DVOM to check for voltage to the ignition module and the positive terminal of the ignition coil. Place the negative lead of your DVOM to a solid ground and use the positive lead to probe the wires running to the ignition module and to the ignition coil.

Step 3If your DVOM shows that voltage is present at both locations, remove the DVOM leads and set the meter aside. Connect the ground lead from the twelve volt test light to the negative terminal on the ignition coil. Have your partner crank the engine over several times. Your test light should flicker on and off. If so, your module is working properly and no further testing is necessary.

Step 4If your test light does not flicker on and off, visually inspect the wires running into and out of the ignition module. Look for burn marks, melted wire insulation and breaks in the wires. Use your wire splicing tool to remove the bad area in the wire and use your wire connectors and splicing tool to repair the faulty wires.

Step 5Use your DVOM to check for an open circuit condition in the primary coil winding. Touch the negative probe to the negative terminal on the ignition coil, touch the positive lead to the positive terminal. Set the meter to read ohms. If the reading shows infinite ohms, your ignition module is faulty and should be replaced. Follow the service manual instructions for replacing your ignition coil.

Step 6If the DVOM test shows low to no ohms, then you have a faulty ignition module that will have to be replaced. Follow the service manual instructions for your year model vehicle to replace the module.


hope this helps