Had a scare the other day while out of town about 40 miles away. All of a sudden, my '05 Element engine started bucking badly at anything above 3000 RPM's. I happened to find a recommended transmission shop near the auto parts store that I stopped in to check on the price of a diagnostic code reader. They had an expensive looking reader that threw a code of P2647. The code translated to "Bad Vtec oil pressure switch" I took a chance and purchased a new switch which is located on the left rear valve cover. A little stretch to get to, but by removing a bracket that holds the power steering hose, you can unscrew it with a 22mm socket and extension. The switch and a new o-ring cost $72 with tax. I removed the old one and screwed in the new one, a 10 minute job. Started it up and Fixed!! Honda wanted $190 labor plus the cost of the part. Apparently this is a common failure for the switch. I read some other posts about cleaning the switch, oil screen ect, but this did not need to be done in my case. Just a FYI if you are having a problem that matches the symptoms.