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Discussion Starter #1
my 93 bronco with the 302 wont start. i drove it today parked it and came back an hor later and just wouldnt start. i know that the issue is in the "fireing" system because there is no sparks comming from the distributer and there is plentyof fuel getting to the engine.
please help
 

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I scrape on both sides
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trace the spark back.
 

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I scrape on both sides
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nowhere, spark starts at the coil, its a step up transformer. so if your not even getting spark from the coil, id suggest first making sure your getting voltage to the coil and it has a good ground...second id pull out the ohm meter and put it on either side of the wire going from the coil to the distributor and twist it all up while measuring it and if it says OL or OFL at all, then you need to replace that wire because of an open. if you dont have an open in the wire, check the coil... primary windings should be minimal resistance, so pull the coil out and where the connector plugs into the bottom put your ohm meter across there and it should read i believe 7-15 ohms if that... might actually be more.. cant remember.. eoither way.. report back with that.... then take your oh meter and measure from the negative side of the primary circuit and the tip of the ignition coil.... should read in KOhms... and let us know what you get back
 

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my 93 bronco with the 302 wont start. i drove it today parked it and came back an hor later and just wouldnt start. i know that the issue is in the "fireing" system because there is no sparks comming from the distributer and there is plentyof fuel getting to the engine.
please help
Your engine at it's most basic form only needs three things. Air, fuel, fire (spark). How do you know there is no spark (how did you test that?) How do you know your getting plenty of fuel, did you test pressure?

Also, did it fire back up after cooling off now?
 

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Sorry, but I personally can't walk you through testing the ignition system without referring to the same reference sources you can buy for about $20. There are others on this site who can, and have done so many times for others in your situation. You might search for posts by miesk5, seattle FSB, mikey350, and steve83, and search for TFI
 

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Discussion Starter #8
wierd...
after letting it sit overnight it fired right up
have'nt driven it far because im worried it might not restart but after 20 minutes of iddleing so it was at full temp, it turnd off and on smoothly
2 hours later i went back out and it wouldnt start again it just cranked and woulndnt catch
i know that there was no spark when it wouldnt start because i removed a plug and watched it while trying to start it (i know there is also air and fuel getting to the engine)
im very confused about what could selectivly make it not start and later start.
 

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When it was running, did it have the "Check Engine" light on? The ignition system is computer controlled, maybe the computer is trying to tell you where to start to look.
 

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TFI or the pickup in the dizzy
 

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Discussion Starter #12
thanks for all the replys
i plan on replacing the TFI ICM tomorow to try and solve this,
as it is a computer is it possible to buy a TFI ICM that is programed for different things(power or fuel economy)
 

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I would check the coil as mentioned by others. The coil went on a tempo I had many years ago. It stalled out out day. It would start fine, but would die after switching from park to drive. After it cooled down it would run for about 5-10mins then do the same thing. I replaced the coil and it ran great for months.

I would figure that a broken coil would prevent the engine from starting and running, but i guess it could be intermittent.
 

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Perhaps a bad/flaky EEC relay? When you turn the key to on/run the CEL is supposed to light and stay lit while cranking until the PCM gets a PIP signal while cranking or running. When it doesn't start, does your CEL light, and then go off while cranking?

Could also be a poor quality ground at the driver's side upper radiator support.

Regarding the TFI, that can be removed and tested at a parts store. I agree with others, that may be your problem.

A weak coil may fail when it gets hot, or sometimes just while it is under load.
 

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Discussion Starter #15
update:
i have instaled a new icm, coil, and spark plug wires and it seems that my problem has gotton worse.
when i now start it the engine starts to sputter,
the only issue that i have found within the systemis that the wires that lead to the coil have about 11 volts running through them and i read somewhere that they should have 6-8v could this be the problem
 

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hopefully you have gotten the correct TFI module.

 
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