Is it necessary to push on the gas to start a car or can the key be put in the ignition and turned without touching the gas pedal?
You shouldn't have to feed gas to start an engine. Most modern cars will feed the necessary amount of fuel into the ignition without pumping the gas petal at all. If you find that you have to pump extra gas into your engine for it to start, there are a few possible issues you can address. A: fuel pump / lines are dirty and need to be flushed or cleaned, B: Needs a simple tune-up to replace spark plugs / wires so they fire more efficiently.
That all depends on the year of the vehicle.
Depends on the vehicle. Carburated vehicles yes. Fuel injected vehicles no. If fact, pumping the gas pedal on a fuel injected vehicle does absolutely nothing but admit more air to the engine while starting. HTH. -Jim
Do not forget the air filter.