'79 Ford LTD

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  #1  
Old 03-29-08, 09:08 AM
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Smile '79 Ford LTD

Hi,

Car will not start as long as your holding the key to try to start it.
When you release the key, it starts.

Any clues, anyone.

Thanks
Gary
 
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Old 03-29-08, 09:35 AM
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could be a few things like a pickup in the distributer or ignition module or suppose it could even be an ignition switch also, would check for power at the ignition module 2 wire connector one should have power while cranking the other with the key in the on position if you have both of these would suspect a pickup or module.
 
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Old 03-29-08, 11:19 AM
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The problem sounds more mysterious than it actually is. At "start" you need both current to the starter and current going to the ignition, at the same time. YOU don't have that (at least in it's fullest capacity). But you DO have total current flow to ignition when in JUST the "on" position.

This is sort of like how you can get a manual transmission car to start, whose battery is not supplying good current, -but by rotating the engine (like by pushing the car and popping the clutch) with the key "on", the car will fire off. In essense, you are doing that with yours. YOU are able to 'rotate' the engine with the key when in "start" position, and then when you are taking advantage of the engine being rotated, by letting the key fall back to "on", all the available current goes to the ignition and it starts.

I have noticed with many vehicles I have owned over the years, that if a vehicle just will not fire off, say in the cold of winter, after it rotates and rotates, - that if I release the key back to "on", often then it will start.

I realize this does not help you pinpoint your problem (although the concept may help provide clues). Bejay already provided ideas. I just wanted to point out some of the theory.

Also, years ago, I remember hearing that during the "start": position, the current would go thru some kind of resistor. However I can't seem to find any material on this, or if this is true, or if this still applies today or not. If there were some kind of resistor in the start circuit, this may be a place to look. Anybody know anything about this?
 
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Old 03-29-08, 01:48 PM
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Hello guys,

Thanks for the response. We have a new entire distributer, coil, & module installed. Fire is going to the distributer when turning over the engine.

Thanks again,
Gary
 
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Old 03-29-08, 03:08 PM
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What about coming OUT of the distributor as high secondary voltage?
 
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Old 03-29-08, 03:47 PM
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high secondary voltage?

sorry, i am not a mechanic... don't know what that means?

Thanks
Gary
 
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Old 03-29-08, 04:14 PM
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Well, battery voltage to everything on the car that does not spark at the plugs is 12.6-14.5 or so volts, and is primary voltage. But the sparking voltage is like 20,000 volts or so, because it is transformed with lots and lots of windings, like a miles worth, and is called secondary voltage.

So, do you have any spark coming out of a coil wire or plug wires? Even if it is just one?
 
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Old 03-29-08, 07:59 PM
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the only thing on your car that would keep it from running is basicly the ignition system it is the only thing controlled by the ignition switch, the engine would still be getting fuel from the carb regardless of where the key position was.
if you do a spark test you will probably find you do not have spark from the coil wire. while the engine is cranking over and you might see a few sparks once the key is released, by your description that is when the vehicle starts when you let off the key.
if you use a test light or voltmeter you can check for voltage to the ignition module check both with the key in the start and key on position if you are missing one of the above, you should probably check the ignition switch if you have voltage at both wires would go straight to the pickup or module usually it is the pickup that causes it only to fire when you let off the key but it could be either one.
might look up a wiring diagram may help you to test the voltage even though wire colors may vary they are all similar and there are several online for the duraspark ignition system. heres one and im sure autozones website has one also
http://www.jason.fletcher.net/tech/d.../duraspark.htm
 
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Old 03-30-08, 06:49 AM
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It's a doozie

Hi again,
I do have sparks from the coil wire. I unplugged the coil wire, inserted a spark plug. While my dad is turning over the engine the plug does have good fire. It's not that the car won't run... it runs really good. It just won't start while we are cranking it over until you release the key. Like i said earlier, we have a new coil,new distributer assembly with pickup, new module, new voltage regulator and yesterday we check the timing with the gun on wire #1.

Won't start until you stop trying. Weird....

Thanks again guys,
Gary
 
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Old 03-30-08, 02:43 PM
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Question

on the old cars(which i am more familiar with) there was a ballast resistor that allowed the car to start on 12 volts and run on 8 volts.(it saved wear and tear on the points-i said OLD CARS!). on later models, there was a RESISTOR wire that served somewhat of the same purpose. check the voltage at the coil with the key in start position and at run position. should be the same. if memory serves, there is a switch box at the base of the steering column with a rod running to it from the key area. this CAN get out of adjustment. post back!
 
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