Tie rod ends are just the physical linkage between the steering gear and the spindles / wheels. They don't have any idea that power steering is even on the car or whether it's working. The only thing that could happen is the inner tie rod end is rotated one way as far as possible, and the outer is rotated as far as possible the other way. That would make the entire linkage unable to swivel as the steering system moves left and right or the suspension system moves up and down. In rare cases that binding would resist the movement of the steering linkage, and system. That would be evident right away when the car was taken for the test-drive after the alignment. It wouldn't show up six months later, and it wouldn't be intermittent.
On your car, the inner tie rod end can't swivel. It's bolted to a center take-off steering gear through that rubber bushing. The outer tie rod end is still of the normal ball and socket design that will swivel as necessary. The threaded joint, or connection, between the two ends, was tightened on earlier models with a jamb nut. With that design, you have to watch that the outer end doesn't swivel to the end of its travel when you tighten that nut. '98 models have a different design where you tighten a clamp. There's no worry about the outer tie rod end swiveling. The alignment specialist just has to watch that it's centered after the last adjustment when the clamp is tightened.
What you're describing sounds more like a very common problem GM had with their rack and pinion power steering gears in the '80s. It was called "morning sickness" because the problem always started out with the loss of power steering assist in just one direction, first thing in the morning, when the engine was still cold. At first that loss of assist would last less than about 15 to 20 seconds, then it would be fine the rest of the day. That loss of assist got longer and longer every day, then it would start to affect turning in the other direction too. This was caused by the Teflon sealing rings on the spool valve grinding grooves into the soft aluminum housing, then pressurized power steering fluid could bypass that valve rather than being routed to push on the power piston to provide the power assist. That can happen on any car brand or model with a rack and pinion steering gear, but it is not very common, and no other manufacturer had the huge failure rate that GM did. The aftermarket industry came up with a simple solution to that problem, so it rarely occurs with remanufactured steering gears.
Since this is so uncommon, the best course of action would be to connect an inline pressure gauge between the power steering pump and the steering gear. That assembly has a valve on it that can block fluid flow. The gauge will show the "dead head" pressure which is the maximum the pump can develop. That must only be done for a couple of seconds; just long enough to take the reading. Normal maximum pressure is 1250 to 1350 psi. Power steering systems don't build full pressure until it's needed, so the first step is to see what the pressure is when you observe the loss of power assist. If pressure is low at that time, it has to be because the pump can't develop enough pressure or there's excessive internal leakage inside the steering gear. That's when you momentarily close the valve on the test gauge to see if the proper pressure can be developed. If it is still low, suspect worn vanes in the pump. We don't fix them. The pump gets replaced. Most often that will cause more trouble than you described, and it will affect turning both ways all the time.
If the pump can develop normal pressure, but it drops when the test valve is opened, there's excessive leakage inside the steering gear. You'll likely see the pressure drop even more when a helper turns the steering wheel while the hard steering is occurring.
If you want to simply replace a part as a test, which we don't like doing, I guess I'd start with the pump. Both parts have a very low failure rate, but the pump is much easier to replace. I did run into a few in the early '90s that developed worn vanes which reduced the pressure they were able to develop. Logic would dictate a weak pump will cause loss of power assist both ways, but this is one place where logic fails us. It can take different pressures to turn different directions. If you need, for example, 500 psi to turn left, 550 psi to turn right, and the pump can only develop 525 psi, it's weak but still able to meet the needs for turning left. That wear will get worse, so if you don't do anything for now, eventually you'll lose the power assist to the left too. Unfortunately that is the same set of symptoms and observations when the sealing rings in the steering gear are leaking. The biggest clue is with leaking sealing rings, they expand and seal better when they get hot, which will happen from the hot fluid. Weak pumps generally don't get better when they warm up.
You might take a look at this article too for more information:
https://www.2carpros.com/articles/power-steering-problems
If you're going to replace the pump, I can post the directions, with drawings, from the service manual for you if that will help.
Mar 4, 2021 at 10:54 AM
