Here's a couple of quick and easy things to check.

1) Is the air meter plate moving freely?
2) Is there a lot of slop in your accelerator linkage and dried out grease?
3) Have you done a fuel pressure test?
4) Have you ruled out vacuum leaks?
5) Have you checked your temperature sensors?
6) Is there soot in your tailpipe or other evidence of running rich?
7) Are there any carbon tracks or other signs of coil deterioration?

What do the plugs look like when you pull them out?

Those are some good easy things to check. If you aren't sure how to do those things, please ask!

-tp