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Alright i took off the cap to see if somthing metal would stick to the wheel and it does could this be my problen with how my truck is run the poor idle ?
 

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yo Cole,
Yes!
Misfiring, Rough Idle, Surge, & Ping-Knock Symptoms, due to a Magnetized Shutter Wheel, (Bronco & all Fords w/EEC IV & TFI); "...Inside the TFI distributor is a Hall-Effect sensor that provides an RPM and POSITION signal to the Ignition module and ECM for fuel and ignition control. Mounted to the distributor shaft is a "shutter-wheel" that passes through the Hall-Effect sensor. The slots or windows cut in the shutter-wheel are what makes the Hall-Effect sensor switch on/off to create the signal it sends out. The shutter-wheel is supposed to be a piece of "dead" steel but can become magnetized. A magnetized wheel can cause very erratic operation of the Hall-Effect and resulting erratic output signal. The Test: There are a couple of ways to check for this condition. One is to simply pull off the distributor cap and see if something steel will "stick" to the shutter-wheel. Make sure that whatever you are using to check the wheel with isn't magnetized itself. A more accurate method would be to watch the wave-form on the "SPOUT" wire with a Vantage or Lab-Scope. The SPOUT is the wire with the connector in it that you unplug to set ignition timing. Monitor the wave-pattern on the SPOUT with the timing-connector in. If there is anything erratic about the wave-form, unplug the timing connector and re-check the wave-form. If the pattern "cleans up" all of a sudden, chances are good that you have a magnetized shutter-wheel. The Fix: Most shutter-wheels can be removed from the distributor shaft with a couple of screws. Everybody seems to have their own way of de-magnetizing the wheels but good success has been had with bulk audio-tape erasers or by placing the wheel in an engine parts cleaning oven and baking it. That last one sounds weird but it works..." Scroll down
Source: by snapon.com via archive.org @ Misfiring, Rough Idle, Surge, & Ping-Knock Symptoms, due to a Magnetized Shutter Wheel, (Bronco & all Fords w/EEC IV & TFI); "...Inside the TFI distributor is a Hall-Effect sensor that provides an RPM and POSITION signal to the Ignition module and ECM for fuel and ignition control. Mounted to the distributor shaft is a "shutter-wheel" that passes through the Hall-Effect sensor. The slots or windows cut in the shutter-wheel are what makes the Hall-Effect sensor switch on/off to create the signal it sends out. The shutter-wheel is supposed to be a piece of "dead" steel but can become magnetized. A magnetized wheel can cause very erratic operation of the Hall-Effect and resulting erratic output signal. The Test: There are a couple of ways to check for this condition. One is to simply pull off the distributor cap and see if something steel will "stick" to the shutter-wheel. Make sure that whatever you are using to check the wheel with isn't magnetized itself. A more accurate method would be to watch the wave-form on the "SPOUT" wire with a Vantage or Lab-Scope. The SPOUT is the wire with the connector in it that you unplug to set ignition timing. Monitor the wave-pattern on the SPOUT with the timing-connector in. If there is anything erratic about the wave-form, unplug the timing connector and re-check the wave-form. If the pattern "cleans up" all of a sudden, chances are good that you have a magnetized shutter-wheel. The Fix: Most shutter-wheels can be removed from the distributor shaft with a couple of screws. Everybody seems to have their own way of de-magnetizing the wheels but good success has been had with bulk audio-tape erasers or by placing the wheel in an engine parts cleaning oven and baking it. That last one sounds weird but it works..." Scroll down
Source: by snapon.com via http://web.archive.org/web/20020806143543/http://www.snapon.com/newsletter/sonews_08_2002.asp


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"While this may seem strange, magnetized shutter wheels inside of Ford distributors have been a recurring problem. Exactly why the shutter wheel becomes magnetized is not apparent. I suspect the armature radiates magnetic energy that eventually magnetizes the shutter wheel. Even worse, this problem can be very difficult to track down.

When this problem was run by the STS Technical Review Committee, Dan Buckley replied, “Supposedly, most models with the TFI-IV Ford ignition are subject to this problem. Most techs have reported long PIP duty cycle and rounded PIP waves as clues to this problem. Whether the problem be magnetization or a bad hall effect, the SPOUT becomes erratic.”
We thank Dan for providing two very excellent scope patterns showing both good and bad PIP signals (See Illustration #1 & #2). The PIP (Profile Ignition Pickup) is at the top pattern and SPOUT (return signal from the computer to the distributor module) is just below it. The bottom pattern is the ignition coil. Illustration #1 shows a bad PIP pattern.
On illustration #1, note the skinny signature PIP (1), double SPOUT (2), erratic timing advance (compare the vertical dashed lines between the PIP and SPOUT patterns) and the missing coil firing (3). With a missing firing event, can you understand why this would cause high HC emissions?

Illustration #2 shows a fatter PIP signature (1) with all the other signal patterns being normal. Also, note the consistent timing advance and regular, even coil firing.

If you come across a Ford distributor Hall-effect shutter wheel with this problem, you won’t find them available (at least I couldn’t get one). To try and save time and money, you might want to try heat-treating the rotor in order to demagnetize it. Probably the simplest way to accomplish this is to simply have your local machine shop put it in the engine block cleaning oven."

by T Moss at thttp://forums.corral.net/forums/eec-tech/928014-eec-wiring-diagram-question.html
Illustrations are missing.
 
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