There is a box thing just under the clutch master cylinder on the firewall under the hood. That is the computer. There is at least one harness of wires that comes out of it. That is where I would start in your case, make sure there is that contact grease in there and that there isn't a bunch of water. I'd also make sure the wires are intact and not shorting out. Same goes under the dash up around the fuse block and in that area. Next would be checking all of your wiring harnesses under the dash for a frayed line. Then I would start digging around for ground lines..... Lastly, check the relays. You have at least one that could cause this if I remember right.... You should be able to switch the relays out with eachother as they should be the same.
After all this, I'd have the dealer or an auto-electrical specialist deal with it... have them check the computer out to make sure it is okay, then pull your hair out.