Why would the ignition coil on a Cadillac DeVille 4.9 be overheating?

Answer by  bug57 (1048)

Increased resistance in the ignition circuit is the most likely cause. Start with the easiest fixes first: replace the spark plugs, making sure to have the correct spark gap. Replace spark plug wires with new wires. Check all connections for corrosion, and clean them and apply dielectric grease. Check ALL system grounds.

Answer by  tkarlav (1502)

The design of the cadillac 4.9 placed the coil in a very hot spot, under the intake smack dab in the center of the valley. Heat from the engine stays trapped here and can overheat the coil causing failure.

Answer by  ben43 (121)

you probably have a short somewhere. check the plug wires with a good multimeter see how much the resistance is. I dont know what the resistance is for your wires but generally it s 5k resistance. so that is where i would start but other than wires i dont know what else it could be.

Answer by  pfcjoker223 (79)

ignition coils will overheat when they are going out because the material used to insulate the coils of wire inside are breaking down and allowing the coils to short out.

Answer by  Amber40 (24961)

It could be doing this because of two reasons. Either the coil itself is going bad and this is creating heat or something around the coil is radiating heat towards the coil. Make sure the coil is in the right place away from heat and that it is working correctly.

Answer by  rusty94 (123)

it could be because you leave the engine off, but keep the ignition on, this can cause overheating, it would be best to replace the coil with a different brand of after market coils because they all function differently, and this usually solves most overheating problems. your problem is solved

Answer by  billyb (562)

you need to check and see if one of the plugs is fouling out. also you need to check the coil to see if is shorting out. something may be drawing voltage from the coil.