Non-Power Steering

[sdpatt]

I had an absolute blast driving around the Texas World Speedway's 2.9-mile road course this last weekend, but my session was ended durnig the slower parade laps at lunchtime on the second day when the power steering went out, then came back in, then went out again. This occurred for a few minutes until the power assist stayed out for good. I assembled my gear and made the 200-mile trip home to Dallas without the now very appreciated power assist in the steering system.

The inspections we conducted at the track found the PS belt on, the pump spinning smoothly, the PS fluid full and honey colored, no PS system leaks, and no apparent flow into the reservoir with the engine running. I can hear fluid sounds through the glovebox area when the engine is idling, but have not yet confirmed if it is the pump not pumping or the rack not taking advantage of the pump's output.

The rack is a remanufactured unit that has a lifetime warranty, but I do not want to replace it unless Iknow that is the problem as the job is not much fun. The pump is original.

Before I check farther, does anyone have any diagnostic information to help me check this problem out?

 

[Rockledge]

FWIW, I have the "STEERING VERY DIFFICULT/VERY EASY" pinpoint tests for a '95 in PDF format which I could email to you. I think the '95 has the same steering system as your '91, maybe you can confirm that.

IIRC, didn't you replace the rack a year or two ago?

 

[projectSHO89]

Scott,

The "correct" diagnostic procedure involves hooking a power steering analyzer (a Rotunda device) into the system at the rack pressure connector in order to measure pump output, both pressure and volume. Those things are both rare and expensive.

Based on your symptoms, I'd suspect the pump has quit generating pressure in the system or there is a restriction in the high pressure line.

Unfortunately, without the analyzer, I can't think of a useful test to pinpoint the fault other than disconnecting the pressure line at the rack and seeing if you can get some fluid volume/pressure at engine cranking speed. Pretty messy proposition...

Steve

 

[sdpatt]

FWIW, I have the "STEERING VERY DIFFICULT/VERY EASY" pinpoint tests for a '95 in PDF format which I could email to you. I think the '95 has the same steering system as your '91, maybe you can confirm that.

IIRC, didn't you replace the rack a year or two ago?

Yes, I did replace the rack a couple of years ago, but with a remanufactured, non-SHO specific rack. It had been working fine until the hard use at the rather high speed TWS track. It has a lifetime warranty (free except for the alignment) and I can get a used PS pump quite inexpensively. I just don't want to swap either unless I know it is the faulted component. i know how much fun the rack job is(n't) and I have heard that the pump is just as challenging.

If you would, please email the PDF file to [email protected].

 

[rangerj]

SDP,

Just some shade tree diagnostic thoughts:

The rebuilt racks are usually bored and "sleeved" with a stainless steel sleeve. They are much less prone to failure (wear) than the original unit. You may want to ask the 'source" about the failure rate of their rebuilt racks.

Given the high milage on your car, and the fact that the power steering pump is original, it would be my number 1 suspect. Without being able to pressure and volume test the pump it would be an educated guess. At 300K + the pump vanes have to be worn. That being said, it could also be a simple as a pressure check valve or blockage in the line(s). Please let us know what you find out.

 

[sdpatt]

The loss of power assistance came and went like a switch was being turned on and off. There was not a gradual loss of assist. It was either there or it wasn't over approximately 5-6 cycles.

 

[sdpatt]

Anyone have a power steering pump stop pumping?

I'm afraid that the culprit of my car's lack of power steering is the power steering pump. Has anyone had a power steering pump just stop pumping? Were there any indications other than the steering became a real arm and shoulder workout? Noises? Fluid changes?