Ground Explosion expression issue
I purchased the Ground Explosion tutorials by Alex Alvarez and I'm having trouble with my animation. I'm creating an animation of a car being hit my a missile and then exploding with an aerial shot of cars driving on a highway. My debris emitter has 2 keyframes on it at frame 13 with a value of 500 and at frame 23 with a value of 0. I have this timed with the background plate in which I have the car to be destroyed keyed out at frame 13. I will then animate visibilty on a 3D model of a destroyed car to replace the car keyed out of my footage.
I followed all the steps in the videos with no issues until I added and created the expression for the Per-Point Emission Rate to my Smoke Trail Emitter. The smoke trail particles don't start emitting until frame 23. I tried setting the start frame for the smoke trail particles to 13 but it changed nothing. What am I doing wrong? Is there an expression I can create to counter this and force them to emit at frame 13 with my instanced particles?
Please help as this is for a final project for a class and is due in a couple of weeks.