Problems Associated with Your Ford Escape Ignition Coil and How to Troubleshoot Them
Your Ford Escape ignition coil is the main power source for the engine and the ignition system, so any problem with the coil can lead to poor engine performance. You'll also notice a big drop in the vehicle's gas mileage. Here are some of the problems related to ignition coils and the steps in diagnosing them:
Loose coil wire connections
If your Ford Escape's engine is showing occasional misfires, or if it's bogging down and starting up again, that means you have a faulty ignition coil. Once the coil wire connections have been loosened from their connection points, the engine can temporarily cut out as the vehicle hits road bumps or passes over rough roads. If this is the case with your ride, open the hood and locate the ignition coil. There should be a thin positive wire and a thin negative wire hooked up to the face of the coil. The negative wire is connected to ground while the other wire accepts battery voltage. Inspect both connections and make sure they're clean and tight.
Problems with high-tension wire
A high-tension wire that has corroded or has developed high resistance at the connection points can cause a weak or intermittent spark while a wire that has shorted out can lead to a no-start condition. An ohmmeter can be used to check the high-tension wire for high resistance; any resistance detected indicates a bad wire.
An overheating coil can cause the ignition cooling oil to boil and burst through the outer coil casing, causing it to leak. This kind of defect is easy to identify because all you need to do is to look for a wet, oil-soaked coil with melted casing. There are also times when an overheating coil doesn't burst the casing but is extremely hot to touch. You can determine it by simply touching the ignition coil.
Shorted ignition coil
No spark or no-start condition indicates shorted ignition coil. This can be diagnosed by disconnecting the high-tension wire from the distributor and connecting a spark plug to the end of the said wire. An extra wire should be used to screw onto the spark plug's threads. The thin ground wire should be disconnected from the coil face, and the other end of the spark plug ground wire must be connected to the ignition coil's negative terminal before setting the key to the "ON" position. The opposite end of the negative coil wire should be tapped onto a good grounding surface. At each tap, watch out for hot, blue-white sparks at the spark plug electrode. Absence of sparks signifies a shorted coil.