Check the computer codes - click here for instructions. Often, the computer will know what is wrong, but it is not infallible.
Next, turn the key and listen carefully. On most cars, you can hear the electric fuel pump engage for a second or two as soon as you move the key from OFF to RUN (not START - it will still engage but you might not hear it). If you do not hear that, there may be a failed relay, fuse, or fusible link, or even a bad fuel pump. You might want to try testing your car for this before it refuses to start, so you will know whether you can hear it or not. (If you can fold down your rear seats, and you have a sedan or hatchback, do so - the fuel pump is in the back).
If the engine turns over, you may want to check for a broken timing belt. On many cars, you can peek in and see the timing belt directly. That is not the most likely problem. Most Chrysler engines can deal with broken timing belts easily, and without the loss of the valve train and pistons!
Try disconnecting the MAP sensor, which can cause a car to not start without setting any fault codes! If you disconnect it completely, the car may start, in which case it is definitely the MAP sensor.
Another common problem is the Hall effect sensor, which tells the computer where the engine is. This is moderately easy and inexpensive to replace (as is the MAP sensor.) Even cars with no distributor use Hall Effect sensors, on the block.
There is also an engine fuse which might have blown - along with various fusible links. Check the owner’s manual to find their location.
Old or bad spark plug wires, especially moist ones, can cause non-starting, and suggested that you check all spark plug wires, check for moisture or carbon tracing in the distributor cap, and consider excessive water in the gas. He also pointed out that a completely clogged catalytic converter and flooding could cause failure to start. Your car's owner's manual should have instructions on what to do if the engine is flooded (has too much gasoline).
A leaky fuel injector or weak fuel pump may also cause problems. To diagnose these, click here.
A common problem: when no electricity was at either coil terminal with the key in ON, but the engine still cranked: "repair the burnt-out fuseable link in the wiring harness next to the left shock tower."
