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I am not sure where to post this question since its not about a mustang or a 5.0 but i cannot seem to find a good forum for my question. I am working or my wifes 2000 Windstar 3.8L and it was throwing a 171 and 174 code wich wound up being a vaccum leak and pcv issue, which i fixed and those codes are gon but now i am getting a P0303 misfire in #3 cylinder, so i found some specs on what the the coil pack should ohm out and it said on the secondary it sould show 6.5k to 11.5k across the spark plug wire holes and my reading were higher at 14k+ on all of them, and the primary should read .3 to 1.0. it is a 4 prong connector 1 being the B+ and the other 3 are (-), so i tested that and it was .2 on one of them and .8 on another and 1.2 on the last. With those readings, does that indicate a bad coil since the specs are pretty far out on the secondary and a little out on the primary? Before i drop 70 bucks on a new coil i wanted to check with yall and get yalls thoughts. How far out of spec is still ok, if at all. and do my readings indicate a bad coil. Thanks sooooooo much in advance.

***Ryan
p.s. i am having a similar issue with my 87 GT's coil having readings that dont really fall into the specified range. same issue possibly?
 

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cheap and easy diagnosis. You can use a spray bottle to spray a soap and water solution on the plugs wires while vehicle is on. If they are arcing the engine will misfire. locate your cylinder #3. remove your spark plug and inspect it. check plug for being soaked in gas, black carbony residue or looking washed (clean). inspect spark plug gap, inspect tip. if it doesn't look too bad (beige kinda a color) put it back in. if not their may be a multiple of things that could be going on. swap the spark plug wire with the number 5 cyl wire. clear the code and go for a ride. if there is something wrong with plug wire it would set a code of p0305 missfire on cyl 5. If all of these if you can't reproduce any of the above, you most likely need a coil. also inspect coil tower for corrosion and if you have and brake cleaner (4.99$) spray around the cylinder 3 area and if the motors rpms increase there may be a vaccum leak in that area. good luck :yelwacko:
 

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Thanks for the reply, i will try and see if i can get the miss to follow the plug and wire. I have a feeling it is gonna be the coil, but i will try everything i can so i dont have to buy anything yet!! thanks so much for the ideas!!

***Ryan
 
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