Have a 96 Explorer ,,Wont start with the switch some times,,

Next time this happens, check the small wire at the solenoid for battery voltage while a helper turnes/holds the key to start. If no voltage, possible ignition switch or that circuit is failing! Now, IF voltage IS present and solenoid does NOT 'click' in, replace it with a premium/HD one, lot of difference in the performance, plus with the V/8 that is what it needs. Not that much more money for the better part!

poss power isssue at solenoid.ck to make sure connection are clean and that you have 12v at solenoid.cables may also be loose

Before you go and replace another solenoid, take a look at your battery. A bad solenoid CAN prevent the car from starting but it CANNOT keep the dash lights from coming on. Make sure the battery is clean. If there is one thing you should keep clean and free of grime, it's the battery. Remove the negative cable and then the positive. What you are looking for is acid corrosion, oxidation, or clamps that are worn out. Corrosion occurs most commonly in, on, and around the clamps. BE CAREFUL! Corrosion is a solid form of sulfuric acid so don't stir it up. Breathe some of that into your nose and you will not be happy. Most battery clamps are made of lead. When sulfuric acid contacts the lead, a chemical reaction occurs and causes the formation of corrosion which is normally white or green in color and appears chalky or somewhat similar to mold in severe cases and left unchecked will destroy paint and burn holes in the metal beneath. The reason it almost always begins at the battery cable clamps is because the point at which the lead post exits the plastic case is not sealed. Acid vapor exits the case at this point and goes right to work on the clamps. In time, the corrosion will actually leech its way from one end of the battery cable to the other and this can be a costly repair. Inspect each clamp carefully because it may not be obvious. Look at the inner surface of the clamp and the surface of the post. Oxidation will cause lead to look very dull and will greatly inhibit conduction of current. A battery post cleaning tool is nice but make sure it uses a wire brush to clean, not a blade. The blade type can remove enough lead from the post that even a new clamp won't get tight. If the corrosion is excessive, replace the clamps. If oxidation is the culprit, clean clamps and posts with the wire brush. Next, find a clean gallon jug and some baking soda (sodium bicarbonate). Fill the jug with warm water and about a half cup of soda and mix thoroughly. Sodium bicarbonate is a base that will neutralize the sulfuric acid. If necessary, pour some solution into another container and submerse the cable end for several minutes. Pour the remaining solution over the battery and any acid will react by bubbling. Keep rinsing until the bubbling stops then rinse with plain water to avoid getting the solution inside the battery vents. Do not pour soda onto the battery and try to add water or you may neutralize the acid on the inside. Bad. Once everything is clean, put it all back together and make sure the clamps are tight and their mating surfaces clean. To help prevent this problem in the future, smear a little grease around the base of the post. Install the clamp and spray paint the clamp and post. Or you can by battery protector but it will stay sticky and collect dirt. Number one rule---keep it clean and your battery will last a long time. If you have any questions, just ask. Good luck