First try to clean your intake throttle Body, with THrottle body cleaner. Remove all air cleaner and hose. Spray inside butterfly. Take fingers and open the butterfly and spray inside and take toothbrush and clean completely. use rag to remove remaining gunk. Starting car will be rough, give it gas to clean up the junk. White smoke will come out because of the cleaner. Will go away after a few seconds. Dont start car inside, or it will smoke up the house.
Please specify how much mileage you have. If you have above 100,000miles, change spark plugs. Put original IRIDIUM plugs.
Try that first.