Hey guys im in the process of getting my h22 more reliable and lately its been acting up. When its cold outside and im driving the car will kind of lag between 2-3500 rpm. I've noticed that also when i put the car in neutral to come to a stop the idle will drop down below 500rpm and slowly come back up. I've replaced the butterfly valve gasket and the throttle body gasket so far. What could cause this. Sometimes the car would even stall out also.