How to Replace the Ignition Coil in a Chevy Impalaby Contributor
On an engine with a distributor ignition system, like the one you find in some Chevy Impala models, the engine starts when the Impala's ignition coil converts the low voltage from the battery into the high voltage needed to spark the spark plugs. When you can't get your car to start, you may need to replace the ignition coil.
Determine whether you have a distributor ignition system. Chevy Impala cars manufactured after 2000 have a distributorless ignition system (DIS), in which case, you need to work with a coil pack, not an igntion coil.
Disconnect the negative battery cable. If you fail to do this, any metal contact from tools may cause a fire or potentially electrocute you.
Locate your Chevy Impala's ignition coil. Typically, the distributor cap contains the ignition coil. For models with an inline 6-cylinder engine, look for an external coil. Remove the ignition lead, or the switch-to-coil lead, from the ignition coil.
Use masking tape or another system to mark which spark plug wires correspond to the appropriate coil high-tension terminal. Your Chevy Impala won't start if you don't correctly reinstall the spark plug wires.
Take out the two screws that attach each ignition coil to the Impala's ignition coil control module. Then, remove the ignition coil(s) and replace with the new coil(s). On 1975 to 1978 engines, you need to use a blunt drift to dislodge the coil wire spade terminals from the distributor cap.
Coat the inside of each plug wire connector with silicone dielectric compound. You may want to clean the connectors before you apply the compound.
Reverse the dismantling steps to reassemble the ignition coil. If you have a torque wrench, you want to tighten the screws to 40 inch pounds (5Nm) of torque.
- The process for removing a coil pack, which you find in a DIS, in a Chevy Impala is similar to the one for an ignition coil. The main difference is the type of wire connections.