Need help troubleshooting Hydraulic Power steering issue

The steering on our 2012 Infiniti G37 went stiff all of a sudden, and im hoping you all can help me at least troubleshoot it because im going to attempt to do it myself.

For context, i brought it to the shop to get a tire replaced after a flat due to cold temperatures.(rear passenger side) The steering was fine and never had any problems, but 1 minute after driving away from the shop i heard a strange noise. It’s hard to describe the noise. It was quiet and subtle but it sounded like a slow squeak which lasted only 1 second. I’m not a mechanic but it sounded like something was trying to turn but couldn’t because of friction, thus the slow squeak.

But anyway, the steering is extremely difficult at low speeds. I can tell that im not getting ANY assistance from the power steering system. I’m thinking its a bad pump but im not sure.

I dont hear any kind of noise from the pump or the belt. There aren’t any leaks and the reservoir has fluid in it. The serpentine belt looks normal and feels like it has the normal amount of tension on it, and i can confirm that its at least spinning the steering pump pulley.

The only thing ive noticed is that increasing the rpm’s made it a little easier to turn, which i tested while it was in park.

What kind of test can I do? And what kind of tests would a mechanic do with this kind of issue? Thanks

That would imply your power steering pump is shot, imo

3 Likes

Your vehicle is over ten years old.

This means they put the vehicle on lift to do the tire replacement.

So, when the vehicle was lowered after that service, one of the upper strut bearings wasn’t happy anymore, and now the strut bearing doesn’t want to turn. Making the steering stiff.

Place your hand on top of the strut tower while moving the steering wheel back and forth to sense any roughness in the bearing.

Tester

4 Likes

After doing the above if nothing found, put the front of the car up on jack stands and see if it is still hard to turn… Or maybe even jack one (front) wheel up at a time and see if that helps, if one side is still hard to turn then that lets you know what side to look at and it shouldn’t be the power steering system…

While jacking the front of the car up, you can also see when the strut starts to drop in the mount, see if one is much more than the other…

1 Like

Check the tire pressures when cold(first thing in the morning or 3 hours not driven).

Make sure all tires are set to or a little above the pressure specified on the drivers door pillar Tire & Load sticker.

You’d be surprised how many customers’ tires aren’t anywhere near those values.

1 Like

Thanks for the replies!

@Tester So i put my hand on the top of the strut tower and had someone turn the wheel but i didn’t feel anything for either side. I will probably have to try test again though because the person turning the wheel didn’t want to turn it too hard because they were scared of breaking something. @davesmopar Mentioned Jacking the car up. My jack isn’t long enough to lift the front end of the car so i had to do it one wheel at a time.

The steering was a lot easier when i did this. It was still stiff, but a much easier. I also didn’t notice a difference in difficulty for either side. Does this fact eliminate the possibility of an upper strut bearing being the problem?

Also, i was looking into the role of the power steering pressure switch, and from what I’ve learned it increases engine rpm depending on the the steering load so that it doesn’t stall. So I turned the wheel in a different car with no steering problems and noticed a slight increase in rpm which is expected. But when i did the same in the infiniti, there was no change in rpm which i found strange.

From what ive researched, a faulty pressure switch would cause the engine to stall because the engine wouldn’t be prepared for the steering load. Yet despite how hard it is to turn in the Infiniti, it doesn’t seem to have any effect on engine rpms. Does this mean that the problem is within the power steering system? Because if it was outside the power steering system, i feel like the increase in steering load would cause some kind of spike in rpms.

Another possibility is a bad lower ball joint.

Tester

1 Like

There isn’t enough hydraulic pressure in the system to trigger the pressure switch. Seems like the pump has failed.

2 Likes

While it seems pretty likely for a newer Infinity, that doesn’t happen on all vehicles . Both of my vehicles have PAS, my Corolla increases the idle rpm when turning the steering wheel, but my truck doesn’t.

As far as what OP should do, all of the ideas above seem like good ones to start with. Since this was noticed immediately after the tire change, seems pretty likely it had something to do w/that service procedure. Could be steering or suspension components. What exactly the problem is, hard to say at this point.

1 Like

Is there any difference turning the wheel with the engine off vs engine running??

1 Like

Unrelated to your steering issue, I hope you have roadside assistance insurance in case of a flat front tire.

1 Like

Pumps tend to last a long time but I did have to replace one, so worth a shot anyway unless paying for a diagnosis. Still there are other front end parts as mentioned that should be checked. If it’s the rack forget doing it yourself. Morning sickness was a Gm thing but well worth paying a pro to do it.

1 Like

It was the pump. I put a new one in today and bled the system. I actually started flushing it but realized the old fluid was still good…i also didn’t have another person to help so there’s that. I learned from every reply so thanks for chiming in!

6 Likes

The follow-up is much appreciated. Glad you “got r dun”

1 Like

You’re welcome

And thank you for posting the update