Should I replace my Coil Pack to solve my hard starting issue when engine gets hot?

1999 MERCURY COUGAR
170,000 MILES
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NILESHEEN
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Hello, I have a 1999 Mercury Cougar with a 2.5L Duratec V6...has approx 170k miles on it. For the duration of time that I have owned the car, I have had problems starting the car after the engine gets hot. I have noticed that when cold (for the most part), the engine will only require a few cranks to get going. However, after periods of driving for 20-40 minutes, when I stop and turn the car off, and then attempt to restart, it will at times require excessive cranking to get the engine fired. At times, I have had to wait approx 15-20 minutes while letting the engine cool off before it would restart. I have checked my fuel pressure at the rail and the PSI numbers I am getting are up to spec (Cranking, While at Idle, under load, etc). I also recently changed my spark plugs and wires, all Motorcraft brand. After doing my own research, I have come across many opinions, but I keep hearing that a bad Coil pack displays many of the same symptoms that I am experiencing. In your best opinion, is this where I should start?

Thanks
Oct 12, 2011 at 7:58 PM
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JACOBANDNICKOLAS
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A weak coil could do what you described, but it would be worse when the engine is cold. What to do is check the spark. You should see a hot blue snapping spark. If it is white or an orange color, it is weak.
Oct 12, 2011 at 9:09 PM