74 Just Stalls
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74 Just Stalls
I Hope I Am In The Right Forum This Time. I Have A 74 Bronco 302 Auto Trans Electronic Ign. Problem Is After Driving About 10mins The Motor Just Cuts Off Like You Turned Key Off, Turn The Key Back To Starts Postion Motor Starts Right Back Up. I Have Tryed (2) Brand New Ign Switches With No Change.
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Joined: Jan 2001
Posts: 57,025
Likes: 2,756
From: Virginia
This problem is going to be tricky to find, since it's intermittent and hard to catch when it does it.
I would get a testlight, and hook it to the coil +, and the engine block. It should light when it's running. Leave it on there and watch it till the engine quits. If the light never went out, then you know your supply to the coil is ok. If you can't get the engine to quit while idling in the driveway, then while it's running, reach under the dash and start wiggling wires around. Also wiggle the wires around under the hood.
If none of this produces any clues, take a hair dryer and with the engine idling, put the hairdryer on the ignition module and see if it will quit.
With the truck idling, take the vacuum line off the distributor. It should have no vacuum. Find an old vacuum line or somehow hook the dist vacuum to manifold vacuum. The engine should speed up. Do this a couple of times and see if the engine tries to quit. Could possibly be a broken wire in the dist.
If none of that produces any results, I would start suspecting a fuel problem.
What I would do first is let it idle for 10 minutes, and see if it cuts off sooner or it takes longer, or it never cuts off.
Then I would run it hard down the freeway and see if it cuts off sooner or later.
If it never cuts off idling, but cuts off sooner on the freeway, I would start suspecting a clogged fuel system, that will barely keep up with the engine.
I would get a testlight, and hook it to the coil +, and the engine block. It should light when it's running. Leave it on there and watch it till the engine quits. If the light never went out, then you know your supply to the coil is ok. If you can't get the engine to quit while idling in the driveway, then while it's running, reach under the dash and start wiggling wires around. Also wiggle the wires around under the hood.
If none of this produces any clues, take a hair dryer and with the engine idling, put the hairdryer on the ignition module and see if it will quit.
With the truck idling, take the vacuum line off the distributor. It should have no vacuum. Find an old vacuum line or somehow hook the dist vacuum to manifold vacuum. The engine should speed up. Do this a couple of times and see if the engine tries to quit. Could possibly be a broken wire in the dist.
If none of that produces any results, I would start suspecting a fuel problem.
What I would do first is let it idle for 10 minutes, and see if it cuts off sooner or it takes longer, or it never cuts off.
Then I would run it hard down the freeway and see if it cuts off sooner or later.
If it never cuts off idling, but cuts off sooner on the freeway, I would start suspecting a clogged fuel system, that will barely keep up with the engine.
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Joined: Jan 2001
Posts: 57,025
Likes: 2,756
From: Virginia
I said heat the ignition module, but you may points?
Anyway, does it take longer to quit if it's idling, compared to if you are running down the road? It may be a fuel problem. The carb stores a certain amount of fuel inside, and if the fuel is barely coming in, it eventually will not keep up. You could see if you have a clogged fuel filter.
Anyway, does it take longer to quit if it's idling, compared to if you are running down the road? It may be a fuel problem. The carb stores a certain amount of fuel inside, and if the fuel is barely coming in, it eventually will not keep up. You could see if you have a clogged fuel filter.
