CEL AND 4000 rpm limit

After two weeks I started my 05 rsx base and the check engine came on. I was fixing the water leak in the cabin. Then I realized that I can't rev more than 4000 rpm. I took to the orielys and they said it's probabely my oil pressure switch or my Vtec pressure switch. Can it be because it's been raining the most of the time it was sitting around?
PLEASE HELP!0

CEL AND 4000 rpm limit