I put an MSD ignition system on my truck it would
not fire since then I replaced all the parts with new
parts and took MSD system off it is still not getting
fire to the spark plug what is the problem
Have you checked the fuse's? Could have blown an ignition fuse, if that checks good then check for power to the coil + side, if you have voltage there with the key on and while cranking then check for a coil trigger signal by unplugging the coil + and - and put the test light between the two, then crank it over and watch for a flashing light, if you have a flashing light then replace the coil, no flashing light, then either the module/pickup coil is bad or you have a broken wiring in the ignition circuit. HTH
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