Remove the EGR valve, spray some carb cleaner into the passage under the EGR valve and let it soak for a while. Use a stiff wire or something suitable used to poke the passage to dislodge the carbon and use compressd air to clear them. Repeat a few times if necessary.
Reinstall EGR valve and retest.
Tuesday, February 2nd, 2010 AT 6:13 AM