w3tc and rest api calls

Hi
I am experimenting with a rest api service. I render books on a website.
When i have w3tc disabled the books drop in one by one or in chunks rather quickly. That is the desired behaviour.
When i enable w3tc the browser waits a long time and then displays the books all at once.
I’ve tried to alter the w3tc settings up and down, disabled the features one by one, until the plugin showed a red message ?The plugin is currently disabled? but no change.
Could there be a conflict with my code and if, what could cause the problem?

My setup is rather simple:
A header
A Form with an Input
A Button that gets the value from the input and triggers a php function
A Footer
Does anyone have an idea what causes the blocking of continous rendering?
regards
theo