Cooling fan speed

Thank you so much for the input you sent me. Now it sounds much better, but what is worrying me now is the fan speed. Yes, when the temp reaches operating level, the fans kicks on but not that fast, not effective enough. I thought we should hear the wiring sound of the fan when is on, isn't it? So why is my fan weak, but when the a/c is on the fans are faster than that, you can actually hear the wiring sound.

Good day. Yes I can spin the two fans freely with a finger pressure. If I connect the fans direct to the battery, then run fast. Some auto guys tried to trace if there is a circut for high speed and couldn't find it. We removed the whole unit and exchanged with the other one and also exchanged the cars and still got the same problem only on my car, the other car runs these fans normal.

When the a/c is on the fans run at higher speed, just by looking and by the wind they blow when you open the hood and stand in front of the car observing.

Thank you, thank you thank you so much guys. Right, the engine is fine so as the head and its gasket. I have travelled over 2000km with this car recently in its condition, no problems. But I have discovered that it is always running at a low temp in highway, that is over 70km the temp gauge needle goes down and stays somewhere at quarter way. Then the car was having some surge or jerk Iike at above 100km/hr. I was forced to do computer diagnosis. I was told there is pressure leak causing temp to be low. And when the car travels for sometime on low temp, some sensors send wrong codes to the computer box causing surges, so I have to look for the pressure leak then cancel the wrong codes, the fans will run at the right speed.