I am sorry to tell you, these auxiliary fans do nothing to support cooling but hindering the air flow to the main fan. I had two of these installed in my 3rd gen and removed after few months. If you want better cooling, keep the condenser clean from derbies/bugs all the time.
Work great for me, I could understand if u wired them wrong and reversed the the flow or the blades were mounted as pullers instead of pushers then ya it wouldn't work for u.