Truck Repair: Chevrolet c2500 son drove in water, c2500, oil level

Question
My son drove my 2003 Chevrolet 2500HD gas p/u into high water (I think at a faster rate than he should have).  He did not have any trouble until later in the evening when he turned the truck off and back on.  The truck check engine light came on, and the dash led shows reduced engine power.  Any suggestions on what it might be?

Answer
Hi Tom,
For beginners, I would remove the air filter and see if there is water in that area. Probably replace the filter if it is wet.
You may have water in a connection someplace, but really, I would expect it to dry out.
Since it didn't lock up the engine, not too much waser went into the intake, but check the filter first.
Also, check the oil level, but I doubt any got in there.
Some WD40 sprayed into some connectors, if you find water in them, will displace the water.

Van