You could have the intake ports plugged up causin EGR flow problems and the flow going to other cylinders and causing it to misfire. Quick way to check this will be to disconnect the vacuum hose at the EGR and drive it. If misfire is gone you will need to remove the upper plenum and clean out the small ports where the EGR flows. Good luck to you and let me know what you find.
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Monday, June 27th, 2011 AT 11:26 PM