I have a part on my intake manifold that squeals and mazda told me they do not sell the part seperately, I will have to replace the whole thing!!! I'm trying to figure out what is the name of this part? The white tab pushes the rod into the mechanism when accelerating and extends when idle. When I'm accelerating the squeal stops. If anyone knows the name of this part please tell me.

Thank you

 

Welcome fuzzzybone!
From what I can tell, that's the vacuum solenoid that controls the secondary air flaps inside the manifold. They look like a std set of 4 butterfly valves that are closed at low speed to improve low end torque, power and mileage. But asthe RPMs climb, they open to allow more fuel and air,and in affect lengthen the intake runners for higher speed efficiency and operation.
This solenoid is controlled byone of the 2vacuum control valves mounted on top of the intake runners, specifically the one on the right side (driver's side, over cylinder #3) as you face the front of the car. It's electrically/electronically controlled to open the port and hence the secondary flaps.
In short and since you hear this only at low speeds and when not calling for power, it sounds to me like you have a vacuum leak in that system some where. It might be as simple as a bad hose, or a bad control valve.
I'd 1) take it back to them again, 2) take it to another dealer, if that's an option for you or 3) write Mazda USA. Tell them you want to speak to the regional service director. I believe this is considered part of the emission control system and should be addressed. IMO, they should be happy to address the issue for you.