Hi,
I have a similar problem.. which has/has not been touched upon in the forums. If anyone has a link that may lead me to a fix, please lead me there

My '99 has the Misfire problem that sometimes gets bad enough to turn on the check engine light. I replaced the Fuel Filter and PCV Valve.. Caused the idle soaring problem and occasional start/die/start/die problem when warm.
I heard about tapping on the fuel rail as a fix on an earlier thread...My question is: Why does tapping on the fuel rail near #5 temporarily fix the problem (1 week or so)? Is there a seal that is not sealing at the base of the injector?
I also heard about replacing the fuel pressure regulator (have not tried this because I question why the tapping thing works.)

If you have any ideas, please let me know. Thanks!