Check 
Spark Plug wires when installing new plugs. Inspect each wire individually, numbering each for identification. Disconnect each wire from the plug and check for corrosion. Clean each wire and check for damage. Disconnect from the distributor and check for corrosion and fit. If new wires are needed, buy a set for your engine model. Replace wires one at a time to maintain firing order. Check the distributor cap and rotor for cracks and worn contacts. Replace if damaged. If reusing the old cap, check the resistance between the wires and the cap. When installing a new cap, transfer wires one at a time to the same location.