Q: Van wont strat after sitting overnight. What could be the problem?

Obviously, there is a fault in either the ignition system, the fuel system, or in the air induction system. If you are truly detecting the odor of gasoline, you might try holding the accelerator pedal firmly to the floor while you crank the engine, thus admitting more air just in case the vehicle is flooded. Sometimes this works, at least as a temporary measure, in cases where the idle air control valve is stuck. In all events, the underlying problem will still need to be diagnosed and repaired, so I recommend that you request a no start diagnostic and the responding certified mechanic will get the engine running for you. With regard to the ignition coil, that should only be replaced if an actual diagnostic, that is testing, reveals that the coil is faulty. Spark plug wires and spark plugs should not be replaced automatically as a consequence of fuel injector malfunctions, if those faults even existed in your case. Spark plugs can get fouled, or damaged by pre-ignition, but that would have to be confirmed on examination. Spark plug wires are not damaged by fuel injector faults. In the event that fuel injectors are diagnosed as malfunctioning, on the car cleaning of injectors is NOT the optimal approach because fuel injectors have replaceable internal filter baskets with very tiny mesh screens. To truly restore fuel injectors to like new condition the injectors must be removed from the fuel rail, sent to a lab such as Mr. Injector, cleaned ultrasonically on a machine, the filter baskets removed and replaced with new filters, and then injector output and spray pattern is measured and documented. On the car cleaning is a quick fix that is sub-optimal and is not the most professional way to handle the problem particularly IF a diagnostic reveals that the injectors are actually partially plugged. If your mechanic is telling you to replace parts, such as the ignition coil, without first performing a proper, complete, and professional diagnosis, you should look for a better trained mechanic. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.