On most nissan motors running gas or LP they have a dash pot that is a vacuum actuated solinoid, that is located on the side of the carb or mixer right above the throttle shaft. When the motor is under a load the vacuum drops and the dash pot will extend and should increase the idle rpm to 1300-1800. If the Tia lift does not have one you should make sure idle is at about 7-750, If it is pnuematic make sure the tire pressure is at max pressure for steering. Make sure the Timing and fuel mixture are set right for your altitude. If it is Electronic fuel injected you will need to go in with a scanner and check the paramaters for the fuel system