Engine completely dies down when gas is applied

[Mechanic—Newbie]

I replaced the battery, distributor cap(not the rotor tho)(should I look into that?) seen someone else posted about they changed their rotor in their distributor. New spark plug wires, Changed the MAP sensor.
I start the car, runs like a dream, but when gas is applied, regardless of pressure, it’s boggs the motor down to almost nothing, then when I let off the gas, it’s comes back to life like nothing changed. I can’t rev it at all, if anyone has had this issue, please help a brotha out! But I haven’t listened for the “fuel pump to prime” so that’s what I’ll be doing when I get back to the car. If that’s a possibility, does it mean the fuel pump is working since it starts the car?? Any advice helps, thanks in advance everyone!

 

[Mr.Baker]

When did this start, have you done any work to the car?
Is this a new car to you? Motor swap? Do you hear any sucking sound?

 

[Mechanic—Newbie]

I just got the car not too long before this post, it was previously worked on by someone else. Swapped “front ends”(not sure if he means motor and all or just the front bumper radiator area) with. 2000 civic, (initially 96). Fuel pump is working, I hear it prime, I don’t necessarily hear the sucking, but when gas is very softly applied, I can rev it up to about 2k rpms, then it acts like I’m not pressing any further, until I stomp on it, and when it catches up with itself it starts going something like whoomm whoomm whoom whomm whoom. Not sure on where to look next. More of a project car that I want to make a race car haha. so nothing super critical rn. But it would be nice to know what the hells going on with it