Popping sounds

I have a Dodge Stratus 1998 and mileage is 121998. Supposedly the engine has been replaced (before my mom bought it) I think the mileage when I first got it was around 112000, transmission was replaced a year or two ago, bearing in the front driver side wheel, tirods been replaced, power steering pump has been replaced, and I want to say possibly the sway bar (or some huge piece that has to do with the front end of my car.) I've only had this car for 2 years. I've been hearing this pop like sound when I press on my break peddle or the accelerator. It started around the time they replaced the front end and power steering pump. It's more the accelerator than the break causing the noise. Once in a while when I let off the accelerator it will pop. It only makes the noise when the break or accelerator is first pressed like if I'm stopped at a light or sign and then go, other wise while just driving it's fine. Any idea?