The dials have dissapeared

does it have the same acceleration at that speed, if it does not accelerate so well it is called a flat spot and will almost certainly need a good mechanic to sort it out
If acceleration remains as good in this range as through the rest of the rev ange add detail and please resubmit

No, the problems which appear after washing the engine are usually temporary. They dissapear when the washing agent or water dry off. You can help your engine regain its funcionality by drying spark plug contacts, and Ignition module contacts.

leaking onto the ground? or 'Dissapearing'?

If 'Dissapearing' it is probably a blown head gasket.
to check: remove the radiator cap while cold, fill the radiator to the top. start the engine. If bubbles of air come out of the radiator cap, the head gasket is blown.

If leaking on the ground, it is most likley a split hose/radiator/pump.
fill the water up, put the cap on, and let the car idle till warm, have the bonnet open, and look for the escaping coolent.

I use to have the same problem until engine warms, I change the oil, oil filter and the air filter and the problem dissapear

Scanner not communicating with the computer is most likely a fuse.

What iI would recommend is to take your car to your local auto parts store that does free electric checks such as Advanced Auto,Autozone,or Checkers and have them retrieve the codes in the on board computer.This will provide you with a starting point as to what repairs need to be made in order to clear the check engine light.

Ensure there is sufficient engine oil, top up if neccesary. If still there the cheapest next thing is to have the oil changed and use a good quality synthetic of the correct grade

sound like you have have "valve chatter"

lose of memory bank in radio , bad part or power surge

the best thing i can think to do in you case is find out if you are loosing the 12v (unlikely) or the ground (more likely) one side of the injector will have a constant 12v. if the 12v is dissapearing under the load then just snip the wire and tie into one of the other injector feeds. they should all share the same fuse anyhow. if it is the groung pulse dissapearing just snip the wire by the injector and the computer and run a new one. shure it might look funny outside the loom but it eliminates all other possibilities. if the problem persists then you are looking at a connector fault or computer.seeing that you have replaced everything else this should get you back on the road. feel free to write back if you have any questions.. dustang