Took my 2006 to get the oil changed today to the local dealer. Picked it up, drove it out if the lot, oil pressure drops to zero at first stop light. Car sounded fine, and pressure shot back to 25psi when i hit the gas. Took it right back to dealer and they cannot figure out the problem. They said they primed it per the instructions several times and the oil is at the proper level. The tech says he doesnt think it is priming. But the guage does go to 25 at throttle then drops to zero at idle. Next step I guess is removing the sending unit and reading the pressure with a direct guage. Any ideas how a sending unit would go bad, or i suppose the gauge itself, just from an oil change? Im presuming the tech isnt correct in his assertion that its failing to prime.