Alui,
What you had checked out isn't necessarily relevant. Mine checked out too--twice--on the bench. It was in the car that it did not work!
Rather than go through the exercise a third time with a third off-brand soleniod, we did the swap.
I don't know if this is your problem, but I had the same thing happen, and the same "It's OK, I checked it out" by the electrical shop. So, reserve the possibility that a bench test won't duplicate exactly, the results you get in the car...