When I'm on the highway or neighborhood roads my car automatically slows down after I accelerate regardless of whether I accelerate a lot or a little, and regardless of my speed. To give you an idea it feels as though the car engages the brakes without me stepping on the brake pedal. It's almost like the engine or whatever propels the car forward is being resistant to any forward motion. It's very weird and troublesome to me as I just had $3,000 worth of repairs done on the car including replacing a dead engine. There is sufficient oil in the car and all other fluids appear to be on level. My check engine light recently came on and the machine reading says that almost all of my cylinders (3 out of 4) are misfiring and need to be replaced and I plan on getting a tune up at the same time. Does any one have any idea of what could be going wrong? The braking that occurs after I accelerate is disturbing because it's so noticeable and being a girl I'm just extra paranoid that something could be going terribly wrong which I would want to address sooner rather than later. I've put too much money into this car already just to have it die out on me or have a serious problem occur that could have been avoided. Thanks for any helpful responses!