Engine 2001 mustang studders/misses

I got a 2001 Ford Mustang 4.6 that just developed a miss after throttling it pretty hard. check engine light came on, diagnosed cylinder 1 misfire. swapped number 1 coil and it leveled out. I drove it for a minute and throttled it again and the miss came back. changed the coil and the same thing happened. took number 1 injector out and cleaned it and installed new o-rings. has 150psi in the cylinder. new plug. coil connector does not appear to be burn or anything. has any one had this issue and if so, what did you do to fix it. it seems like after the coil is put on the engine it runs fine until it gets up to operating temp or its throttled pretty hard.

thanks....
 
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Did you change the plug in cyl #1?

yes. after swapping the coil for a different one it runs fine until you goose it and it starts missing. unhooking the injector or coil on number 1 doesn't change anything which just reaffirms what we already know. can something be causing the coils to go bad under heavy load? like at WOT. maybe theres a ground in there somewhere. when the miss is happening, unhooking the TPS doesn't change anything either. but one would assume that if its a bad TPS it would do it all the time.