FIAT

A: Symptoms of a failing ignition coil include a blinking or illuminated check engine light, engine misfires, rough idling, slower acceleration, reduced fuel economy, and, in some cases, a backfiring exhaust and a gas smell. A failing coil leads to incomplete fuel combustion, causing performance issues and potentially damaging other components like the catalytic converter.

A: To evaluate the ignition coils, measure the resistance between the two pins of the coil. If the coil is functioning properly, the resistance should be between 0.558 and 0.682 ohms, with a tolerance of plus or minus 10 percent based on the weather conditions.

A: Coil style.
Primary resistance.
Turns ratio.
Maximum voltage.

A: You can drive with a bad ignition coil, but it is not recommended for more than a short distance to get to a repair shop, as it can lead to severe and costly damage to your engine, catalytic converter, and potentially other components. Driving with a misfiring cylinder can cause unburned fuel to enter the exhaust, damaging the catalytic converter, diluting the engine oil, and causing premature wear on the cylinder walls and bearings.

A: No, you don't have to replace spark plugs when replacing an ignition coil, but it's often a good idea to do so to avoid future issues or repeat the labor. Worn-out spark plugs can strain ignition coils, causing them to fail prematurely, and replacing them while you already have the area disassembled saves time and effort.

A: Yes, a bad ignition coil can definitely cause a rough idle. A failing ignition coil prevents a spark plug from firing correctly, leading to a misfire and a shaky, uneven engine performance when the vehicle is idling. This incomplete combustion can make the engine feel shaky, and the engine RPMs may also become erratic at idle.