under dash

age(20 years old) and heat,little or no dielectric grease on the ICM.worn spark plugs,bad ignition coil(s)..also>> A misfire condition can destroy the ignition module. If the engine is or has been misfiring, do not install the new ignition module until after the source of the misfire has been corrected. Check the secondary ignition circuit. Plugs, Plug Wires, Coil(s). Also check for any camshaft position sensor troublecodes.

Never seen that "under dash" before!!