HELP....I have a 2007 RXP and get a P0520 code without the engine running. If I run the motor it goes into limp mode as soon as it reaches 3,500 rpm. According to the manual, the ECU is looking for an open on the oil pressure circuit during it's check before starting the engine. I have replaced the oil pressure switch with the new part number replacement and checked the ECU on a known good 2007 RXT. The ECU functions fine on that ski. If I ground the oil pressure plug it does not kick the code or check engine alarm. It's not the oil filter or oil pressure switch since this occurs during the system check before starting the engine. I've checked the 4 ECU grounds. Is there another ground or voltage I should be checking ? Any other idea's ? Thanks....