Hello Everyone! This is my first post on j-body... I am a regular on Club GP and a few car audio sites.

My girlfriend has a 1997 Pontiac Sunfire with the 2.4litre engine. On long drives(usually an hour or longer) the vehicle will suddenly lose power and stall out at stoplights when she goes to push the gas again. It acts almost like a stuck PCV valve... but as I have found this car does not use a PCV valve. In normal city driving(trips shorter than an hour) she never has the problem. The motor in the vehicle has been replaced so I have no way of actually knowing how many miles are on it. It is not throwing a SES light of any kind... the only lights that come on when the car dies out are the battery light and oil light. If there is any more information that would be helpful in diagnosing the problem just let me know.

Anyone have any ideas or suggestions as to what it could be?