[jhirasak]

Jon

You mentioned that you had a LM-2 wideband O2 meter. What does it show from idle to 2500 rpm as you gradually increase the speed? Does it go rich or lean just after idle and then come into normal range as you approach 2000 rpms? It would help to know how your A/F ratio varies as a function of your rpms.

The white plug in #6 suggests that you might also have some debris in that idle circuit. It is worth a check to make sure since you did have debris in other cylinders.

John