After starting the engine, a constant tuk-tuk-tuk sound from the power-steering pump comes on. The sound does not increase or decrease with the revolutions of the engine.
Have you checked the fluid level? If the pump is low on fluid its having to work harder to run and it will cause the pump to eventually fail. Check the fluid level and if its low, top it off and have the leak checked. If the fluid isn't low, then the pump has more than likely prematurely failed
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