Is the engine idle speed dropping extremely low? Is there any noise with the new pump?
Yes, air in the system can cause issues and needs bled out when this type of work is done. Here is a link that explains how one is replaced. What I always do is fill the reservoir with the correct fluid and with the front of the vehicle off the ground and the engine off, I turn the steering fully to the left and then fully to the right several times. Then, I recheck fluid level and add if needed. I do this until the level no longer changes. Then I put the vehicle down and start the engine. If there is noise or an issue, recheck the fluid level. Also, it isn't uncommon for air to be present in the fluid; however, it should go away after a short time.
Here is a link that discusses the most common causes of power steering issues. Take a look.
One last thought. If the new pump didn't come with the pulley attached and you had to install it, make sure it is full seated and not slipping. Pic 1 shows the install of the pulley using a specific type of tool.
Let me know if that is what was done.
Sunday, December 1st, 2019 AT 10:32 PM