I believe my car is having minor problems due to water in the electrical system. For example, the tach will read high RPM's but the engine is running normally (in neutral as well as drive), the CEL comes on occasionally but goes back off, just minor gauge misreadings, and on one occasion, didn't start up right off as usual (took a bit longer). I had taken it to the car wash 3 days ago, and it's been happening since then. So I'm fairly certain it's just water causing a glitch. Question is, where would this water most likely be so I can attempt to dry it out, and hopefully resolve the problem? If it turns out to not be water, what else might it be? Maybe I knocked something loose when washing it, but an overall general observation didn't show anything obvious to be loose.

It's an '01 Old Aurora 3.5, 79,000 mi.

(Yes, I washed under the hood against my better judgement)

The car runs and drives just fine, even during the odd gauge readings.

I have not had any work/modifications/anything done on this car since I have had it (3 mos). No problems either.

Easiest might be Air pressure at electrical connections. If water made it in, air could possibly blow it out. Schematic could help determine areas to concentrate on. Especially
The affected wiring.