Here's the deal. I've recently been battling this problem with my 00 EX where the car hesitates and registers a lean mix on my AFR guage while cruising at about 3000-4000RPM in any gear. It basically feels like there is no combustion going on in the engine. Now I have a VAFC (dyno tuned), MSD ignition, N1 cat back, full race cat, AEM fuel rail and regulator, and AEM cam gear advanced 2deg. I've now replaced the O2 sensor twice, fine tuned my fuel curve with the VAFC, and changed the fuel filter. The plugs and plug wires barely have any mileage on them. The last thing I can think of is that either the ignition box or coil is bad. Have any of you had pblms with the MSD ignitions in the past with boxes going bad? If so how and where should I send it to get it looked at? At any other time whether idle or WOT the car reacts fine and has no hesitation pblms and it's been really hard trying to figure this stuff out so any help would be greatly appreciated.