Trouble Starting RAV4



I have a 2000 RAV4 with 122,000 miles, well maintained and serviced, including a recent tune-up. Both front and rear oxygen sensors ahve been replaced. It has a new water pump and timing belt. In hot weather, cold engine, I have a difficult time starting it - the engine will turn over but I need to “stand” on the gas pedal to keep it from stalling again. This has been a nuisance for several years and seems to be worse this year. Has anyone else had this problem and what to do?