Jeep has recently started stalling. Only stalls at stop signs, red lights, or when stopping behind stopped traffic. Doesn't do it every time I drive, but when it happens it's hard to start. You have to keep it revved up or it dies. It doesn't sputter or anything like that,just dies like you turn the key off.The service engine light does not come on either. Any ideas where to start would help since I'm by no means a mechanic, and its hard to bring it in if it doesn't happen often. Thanks alot for your time.