I'm pretty sure, with three authors, you cite the names every time in the text.
The rules change if there are more authors (with 4-6 I think you cite all the names the first time then use et al. subsequently), with over 6 you use et al. straight away and in the references section name the first 6 and use et al. for the rest. Or something like that. You'll have to check the APA guide, I haven't read it in over 3 years.