97 Camry V6 misfire on cyl 1, 3, 5 after driving through puddle

[eikeland]

A few weeks ago I drove through a pretty big puddle in the road due to some heavy rain that couldn't drain fast enough. I didn't stop in it, but I think something bad happened. A few minutes later the check engine light came on and showed that cyl 1, 3, and 5 misfired. At idle I noticed it wasn't running 100%, but other than that it was fine and I couldn't hear any skipping. If the light didn't come on I probably wouldn't have noticed. I reset the codes a couple of times, but it came back soon after. I then took it to a mechanic, but they couldn't find anything wrong and the light didn't come back on when they had it after they reset it After having it back for a few days, the light came back on. They ran some test with spraying water on the wires, but it didn't come on again.

Any idea what too look for and/or replace? I was thinking about replacing the plugs and wireset, but would like to hear some other opinions before I do anything. It's an older car so I would prefer not to spend too much money on trial and error to find the problem :-)

Thanks