How to Start My 1991 Ford F-150 Without a Keyby Allen Moore
The 1991 Ford F-150 relies on an ignition switch, battery, starter solenoid and starter motor to start the engine. However, you also need a key to start the truck the easy way. Without a key, you can still start the truck, but it requires a bit more effort and caution. The job of the starter solenoid is to send an electric signal to the starter when you turn the ignition switch on with your key. If you don't have a key, but you do have basic auto-repair experience, you can start the 1991 Ford F-150 the hard way.
Open the hood on the 1991 Ford F-150 by hand. Support the hood with the prop rod to prevent it from closing on you.
Shift the F-150 into park, if it isn't already. Depress the parking brake pedal with your foot.
Set the end of the screwdriver on the passenger side terminal on the starter solenoid. The solenoid mounts on the fender well on the passenger side of the F-150's engine bay.
Lower the screwdriver so the blade contacts the driver's side terminal on the starter solenoid while it's still contacting the passenger side terminal; this is known as "jumping the solenoid" and will start the truck. Remove the screwdriver immediately as soon as the engine starts.
Close the hood before driving the F-150.