Key won't start car?

[stangzroastrice]

Ok, we tried to start my friend's 351w swap for the first time today in his 87 GT and all the electronics in the car work and everything and we believe everything is hooked up the starter relay correctly. Anyway, the car turns over fine when i jump the positive side of the relay with a screwdriver but when we try actually using the key to turn over the car, it doesn't do anything. what could be wrong?

 

[TheUser]

sounds like you forgot to hook up the "trigger" wire which comes from the ignition switch through your clutch safety switch/neutral safety switch. It's the little red wire that plugs onto the screw at the top of your starter solonoid.

 

[HISSIN50]

The User is right on - ignition interlock device is not up to par.

you can check for 12 volts at the little trigger wire (slides onto a machine stud shank) and trace backwards.

now if you touch the slide-on connector to the hot side of the starter solenoid and it does not start, that suggests the solenoid (or interlock device) is at fault. right now you are bypassing the solenoid altogether.

good luck.