94 Z28 engine misses when warm

I have a 94 z28 which runs fine when it is cold and warming up. After I drive it about 1/2 and hour or so it starts to miss at 2000 rpms. If you depress the throttle at 2000 rpms 55 mph it jumps and misses. If you floor
it it seems to run okay and take off.
The garage replaced the EGR valve and $220 later it does the exact same thing?
Anyone have the same problem or could give me a guess?
Thanks,
Val
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Has the optispark ever been replaced? I'm on my third one. One was ruined by a leaky water pump dripping onto it.

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I had one replaced. I think that must be the problem. What did it cost you to replace it? The dealer wants $650.
-Val
wrote:

floor
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