My friend had his 2008 F150 L:imited washed and they apparently decided to pressure wash the engine.

Now the check engine light is on, and it runs like crap. At least yesterday, today it won't even start.

Any ideas what broke? The codes said something about the throttle body?>?

 

Sounds like you got the plugs wet along with the coils. The engine needs time to dry out a little. Any time you decide to power wash a vehicle engine you need to keep it running. Take care

 

You may need to open EVERY connector and spray them with WD-40.
The WD stands for WATER DISPLACEMENT.
The electrical system is shorting.
Use a hair dryer to further dry the connectors.
Use an air compressor to blow the water out of the spark plug valleys.
Park it in a heated garage and wait for it to dry out.
Use Bulb Grease when reconnecting things to prevent corrosion.

NEVER, EVER, USE HIGH PRESSURE TO WASH AN ENGINE!!!!!

 

I would leave the hood open overnight (if possible) while it is trying to dry out. Perhaps leave it in the sun during the afternoon and let the sun work on it.

 

I second the idea of opening every connector. But don't use WD40. WD40 is not made for electrical items. It will cause more electrical problems since it is conductive.

Use a product called CorrosionX. It is made to be used on electrical components. We use to displace water and clean our SCADA modules when they get exposed to high humidity or water. We have also used it on live 480VAC contactors.

It non conductive and non destructive.

CorrosionX

Here a great demo of its electrical application.

CorrosionX Demo

 

I stand corrected!
I can't be right every time.