Please help! Starts but doesn't run!

[Trumoo]

Ok,
I did the hei conversion on my 84 ranger and I'm getting close. I now have spark and fuel but when I release my hand from the key it turns off. I'm really hoping I'm just a wire off somewhere!

 

[RonD]

yes, it is a missing wire.

There is a START and separate RUN wire that powers the coil/system.
The START wire only has voltage when key is turned all the way to START
That's the wire you are using for power
You need to find the RUN wire, it is there with the other wires from the old TFI system.
It will have power when key is in RUN and if clutch pedal is in or if automatic trans is in Park/Neutral

 

[adsm08]

You might not be "Missing" the wire so much as have it in the wrong spot.

If you took the wires off the starter relay you may have put them back together wrong. All the wires except the one to the starter go on one big post. The wire to the starter goes on the other big post.

If you put the battery wire by itself and all the others together then you get a situation where the system is only powered in start and it will do exactly what you describe.

 

[Trumoo]

Ok. I got it figured out. In the steering column there is a thing that aligns with another thing to make electric contact. When I would remove my hand from the key it would create a gap between these "things" breaking the circuit. Duct tape is holding it together for now.
So it starts and idles! Yay! But now I put my foot on the gas and it revs then backfires and falls flat. If it's a problem with the carb I'm screwed as I have no idea how that contraption works. Calling it a nite for now.
Thank you all very much for your help!

 

[Big Jim M]

Backfire?
Thru the carb usually means an extremely LEAN condition.
Thru the exhaust most times is an electrical problem.
So which is it? Give us a hint here.
Big Jim

 

[RonD]

That part under the steering column is called the ignition switch.
When the key turns it slides a rod that moves ignition switch into its various positions, making and breaking contacts as you described.


HEI system requires a distributor with vacuum advance, do you have that and is vacuum hooked up correctly.
When you REV the engine the spark timing must change or you won't have much power and you can also get backfires, vacuum advance does that, it rotates the sensor inside the distributor so spark happens earlier or later.

Most vacuum advance distributors use an intake vacuum, so a vacuum source between intake valves and throttle plate, so you can't use a carb vacuum port above throttle plate, only below throttle plate or on the intake manifold itself.

Some did use Ported Vacuum, above throttle plate, you need to look up which one you need on your distributor.

 

[Trumoo]

Hey, it backfires out of the carburetor. Maybe I have the vacuum line hooked up wrong? I will try putting it on the manifold tree. Thank you for the suggestions!