I bought my rx7 a few weeks ago and let's just say it wasnt in the best running shape.. it still needs a lot done, wont start half the time (i'm going to get new plugs and see if it helps) and i just nosticed that the Air Pump is not hooked up at all.. no belt no hoses.. just held on by the bracket.. What exactly does it do? My AC has no belt to it either.. The whole engine only has 1 belt running...

 

the air pump pumps air into the exaust, doesn't need to be hooked up for the motor to run but now you've only got one belt running your water pump so make sure its on there good and look into duel pullys

 

I would say that the previous owner was trying to get more power out of the car. Air pump is for the emissions. If that is disconected perhaps portions of the emissions are not working.
If you only have one belt, then you have no power steering or A/C. If you are going to continue running the car with the current set up. I suggest you carry and extra belt.

 

alright, thanks guys. much appreciated.. and since you said it's for emissions does that mean that the car wont pass smog in CA without it..

 

Not only will the car not pass emissions missing the air pump from functioning properly, but depending on the model and year, you may also be down on HP in the upper ranges.

See the air pump is used to feed the main cat converter to keep it from overheating, but also to activate the aux ports and VDI (Variable Dynamic Intake) on some years. Without it, the car would be down 10-20 HP peak ranges.

 

im retorted....what exactly is/whats the funcationality of the VDI?

 

Quick and simple,

Slap a belt on that air pump. Since especially considering that your in Ca. Your going to have emission problems for days with that rx trust me. What year and type is it any way. 87's and up usually dont run at all with out that pump on. And like what was said before, it also actuates some secondary air ports. Check out your compression. If that's good, you can make that car run great with some hand tools. I did it!!

 

See Rotary engines have a built in supercharger caused by the port closure, sending a shockwave of mixture back up the intake, just at the other rotor starts taking in mixture. The VDI just amplifies that by tuning the runner length for low speed torque and high speed power based on load and RPM.

So removing the air pump on say for example a 89-91 non turbo, and suddenly you loose all that tuning, and wiring it open looses low end torque and wiring it closed looses top end power.

 

That would be incorrect. Removing or disabling the air pump would have nothing to do with the engine running. The only effect would be the losses mentioned above; that the cats would burn out, and on the 89-91 non turbos, the VDI and aux ports would not work.