I brought a coil kit for my car a 2003 gmc envoy im goin to have it tune up what the purpose of a coil kit and how you know if you need a coil kit and what are the symptom if they need to be replace
My car has 16350 miles.
My car's transmission is unknown to me.
Hi and thanks for contacting YourMechanic. Ignition coils for your vehicle are designed to supply voltage to the spark plug. To check if the coil is working, simply unplug the coil when the engine is running. If the engine stumbles, then the coil was working. If there was no change with the coil, then the coil was not working. Before determining if the coil has failed, check the spark plug for any burnt spots. This indicates that the coil is producing too much voltage. This can be caused by the spark plug fouling out, excessive oil or fuel in the cylinder, or the wires to the coil pack have no power. The symptoms of a coil pack failing is the engine having a hard start and the engine having a shake to it with a loss of power. Most of the time, if the coil fails, the computer will sense this and throw an engine light with a code p0351 for primary circuit A and / or p2305 for secondary circuit B. If you need further assistance troubleshooting your ignition system, then seek out a technician, such as one from Your Mechanic, that can assist you with your vehicle.
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