if a code gets hardset then i suppose you can try clearing them but if it stays persistant then the problem is still there and will not clear until it is resolved.

as far as urls go on this site they have it setup to remove any email addresses or website urls that are posted in the main post areas.
you can add a few spaces between the prefix's and then use preview post so see how it looks. If it's still blocked out in preview then work on it some more till you get it to show. you can put your email address in your signature in your personal information and it will allow that to show but they just dont want a bunch of outside websites being posted in the forum i suppose for our own security. just because i have my email in my signature some bots and other folks do feel the need to spam me from here so i do get alot of spam emails from business's trying to sell me stuff but thats what the email filter is for in my email client, they wont do it but once ;o)

I finished blowing out the connectors in the engine bay yesterday. They all looked dry. I blew them out anyway and got no moisture.

I think the stored code in my ecu is causing the problem.

Why cant I post links?

I would pull all the plugs/connectors associated with any sensors and the ECM and blow them out with compressed air to remove any moisture that got in them from the pressure washing.
Then go from there...

It's now too late to suggest this tip...but any time you pressure wash any truck you should always disconnect the power source. Hopefully you did this?

Good luck on your repairs

Answering my own question and sharing some info:

Impco product updates:
http://www.impco.ws/product-updates.asp

Idle adjustment:
http://www.impco.ws/pdf/TSB-167.pdf

Impco ECU interface
http://www.impco.ws/spectrum-test-tools.asp

The taper plug on my carb is impossible to get to as it is right against the hydraulic valve block.

I don't think the Idle adjustment screw tis the proper approach to my problem because the high idle started instantly.

Yesterday I cleaned the crank sensor.
I am waiting for a Ecu interface cable. ($100) My Service shop some how does not have one.

I'm supposed to get a service manual today.

Answering my own question:
http://www.impco.ws/pdf/TSB-167.pdf
There is an idle screw adjustment with the tamper proof cover. The cover is impossible to get to because the hydraulic valve block is in the way.

In my situation I do not believe that this is the proper route because it is not the cause of the problem.

The Idle is ECU controlled and requires a laptop and cable to interface with it.
as shown here:
http://www.impco.ws/spectrum-test-tools.asp

My service center somehow has not ever worked on one of these lifts and does not have the cable. I will have it in a week. Only $100.

yesterday I went through and checked every electrical connector, in the engine bay, for water or other damage. All seemed well.

Disconnecting the battery for an hour does not reset the ecu. MIL light is still on.