Q: When it rains heavy, my car sputters and I have to play with the. gas petal then it wants to take off 1999 Mitsubishi Montero Sport

Hello - given your symptoms and mileage, the throttle position sensor is a likely candidate for this behavior. Check for problem codes first to verify the diagnostic code(s) engine management will provide automatically. Most auto parts stores will do this for you for free on a "time-available" basis. A failed throttle position sensor should be throwing problem codes, and lighting up your Check Engine light. I recommend a loss of power inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.