Fiat Siena 1300 air conditioning

I have a problem with the air conditioning in my Fiat Siena 1300. When I turn it on, the engine RPMs drop and it starts to shake. It's a fuel-injected car, although I've been told it should rev up when it activates. In my case, I don't feel the engine revving up. I would appreciate any help. I'm from Venezuela.

There must be a damaged diaphragm that, when the air conditioner is turned on, produces a minimal acceleration of the engine to compensate for the increased force when the air conditioner compressor engages and the car's alternator demands more power.

That's true, but don't forget to check the condition and charge of your alternator. Maybe it's not sending what it should be, and that's why you have this problem. Check the charge: 14 or 14.5 volts.

Hi friend, I'm also from Venezuela. The suggestions you're giving aren't untrue, but in this case, this vehicle here in Venezuela doesn't have that diaphragm. Only carbureted vehicles have it. First, check the spark plugs before anything else. Then, have the throttle body cleaned. Make sure all the air intakes on the throttle body are clean, and then tell me how it works

Okay, thanks, I'll do that. I already have an idea so the technicians don't rip me off