Suddenly super lean while at cruise

[EclipseGST]

My car was doing the same thing this last week, took out the plugs, cleaned them up a bit and regapped them and it worked just fine. Now its doing it again so I am just going to swap them out. If that doesnt work then I will have to search farther.

Have you tried a new power transister or running a ground strap from it to the firewall? I remember I had a problem like this before where it would only run on the 2nd and 3rd cylinder and it was because the transister wasnt grounded good enough. I'd check that and also make sure its got a good connection with the harness. If you dont know what I am talking about, its the little black box located near your FPR and where the coil pack mounts on the intake manifold.

Hope it helps.