I replaced some parts on my SL2 (front brakes, rebuilt calipers, outer tie rod ends, power steering pump and hoses) and I am having a problem. I have NO power steering, at any speed.

Here is what I know about the "S" series:

SL = rack and pinion manual steering, 4.0 turns "lock to lock", though some units may have had electric power steering upgraded silently and without cost.

SL1 = rack and pinion fluid-driven power steering, 3.33333 turns "lock to lock", 100% power steering all the time.

SL2 = rack and pinion fluid-driven power steering with EVO, 2.66667 turns "lock to lock". AFAIK, EVO (electronic variable orifice) means a solenoid pulls a valve inside the EVO mechanism, that the SL1 power steering pump simply does not have. IIRC, the SL2 has 100% power steering below 50 MPH, and zero power steering above 50 MPH. I have heard that some GM products (Buick?) may have two extra steps between "full power steering" and "zero power steering". But the SL2 was "all or nothing".

I just KNEW I forgot to put the spring back in the EVO mechanism, but now that I have it apart, that turns out NOT to be the case. And I am FAIRLY sure I put the "plunger" back in with the correct orientation (EDIT: I took the EVO apart on a junkyard pump that I never ever took apart before, I can tell by the "rust and the dust", I can confirm correct orientation). I've been around to junkyards over the years, and I've got like 3 of these EVO mechanisms in my basement. The solenoid on the EVO mechanism original to the car has 12.6 or 12.7 ohms resistance, so it SHOULD work. I am planning to spray contact cleaner on the electrical connections and let it dry, then reassemble everything.

If I still have zero power steering, after turning the wheel back and forth several times, does anyone have any advice?

(Yes, I could just attach the hoses without the EVO device, if I have to. My NOS brand-new factory GM pump is set up for SL1 out of the box.)

 

I have now disconnected the EVO wire. The car is just as difficult to steer with the engine off as it is with the engine on. The front of the car is still on jack stands, neither tire touching the garage floor. When the tires touch the garage floor, I can only imagine how difficult it will be to steer !

In a day or two I will remove the EVO module completely and reinstall the power steering hoses as if this car were an SL1. If the difficult steering persists, I'll have to consider the rack and pinion at fault. I will probably get another car (older Honda and Toyota seem to be quality leaders at this point) and demote the green 2001 SL2 to a "project car" or an "occasional use car". I have the original rack and pinion, and I think I can still get a rebuild kit. I don't WANT to do this, but not only is this still a perfectly good car, it is a perfectly good SATURN !

 

Don't try to test by attaching directly to a 12 volt source. The Evo for the power steering operates off a pulse width modulated signal, not a constant signal.

Why did you replace the PS pump?

 

THANK YOU! I think I heard the #1 problem that GM found with throttle-body injectors (like the one on my 2.5-liter 83 Cutlass Ciera) returned thru the dealer network is that they were fried with 12 volts. I have no idea how they were able to detect this.

Okay, I lied in my last post. I used the NOS power steering pump that I mentioned in my first post. It did not have the EVO attached, so it was less work for me. But when I finished putting on the serpentine belt and started it up (front wheels still off the ground), I could tell right away everything was wonderful. After a short road test, it's good.

I'm sorry I won't have the "feel" of the EVO, and I have NO IDEA why the EVO did not work. I sprayed contact cleaner into both parts of the wire connector, it should have worked. At this point, "don't let the good be the enemy of the best" comes to mind.

Why did I change it? Those pesky guys at the quickie lube and oil change place kept pointing out leaks every single oil change, and "suggestive selling" the repair to me. I decided to stop going to that oil change place, AND do the work myself -- new R&P, hoses, pump, and front brakes, since I needed front brakes. (The joke is on them, since they said the CV boot was leaking, and it was not.)

Now that it's running again, the car has 10 year old tires and 33,000 miles on the struts. And I discovered that KYB brand is only good for 40K, so guess what I'm going to be doing in another 7,000 miles?

When I turned the key to the "on" position, engine OFF, and measured the EVO signal, I got 9.55 volts ("Fluke" digital multimeter). It sounds like what you are saying is that it might (or might not) be 12 volts, but it is delivered in bursts, and no analog OR digital meter could show such rapid up and down pulses in voltage, and the Fluke displayed some sort of average. That sounds right to me.

I'm thinking of getting a 2012 or 2013 Accord 2.4-liter (~150K miles) for $8K. Arthritis in my shoulders, 25 years of Saturn stickshift, I could use an automatic. Maybe I don't need to be fearful of the CVT Honda and Toyota started using around 2014, but I am. I'll get the old 4-speed automatic.

I thought I put the spring on the wrong side of the plunger inside the EVO unit when I curiously took it apart and examined it, but I found a GM PDF online that talks about the 1997 S-10 power steering pump, and clearly the spring goes UNDER the plunger, where I put it.

We may never know why the assembly-line original EVO unit didn't work when I reassembled everything. Do I need to mark this thread as "solved"?

 

So you lied....nice.
Just kidding...we all do it w o meaning to.

Was the pump really leaking or was that BS from the oil jocks too?

The Evo likely was torched/wrecked before you messed with it, or the internals weren't reset quite right.

As to how they figured out 12V DC would wreck it, the new tech probably trashed 5 of them trying to troubleshoot a vehicle....and they told two friends ......

Not really solved.... let's call it a custom EVO delete

 

The EVO unit is the original assembly line unit. I thought I read somewhere else that you need to turn the steering wheel 15X right and left, and I probably only did so 10X. But I do believe 10X should have been enough. If it was going to work, I should have seen some improvement by the tenth time.

The quickie-lube people suggested the right-side outer CV boot was leaking. It wasn't. Looking at the fluid moisture on the under-hood insulation, it was not hard to figure out it was the power steering pump. The R&P might have been leaking as well. After 20+ years, two things are certain with cars. The possibility of power steering leaks, and that trip to Wal-Mart to get a steering wheel cover, because that was degrading also. I think the dark fluid represents bits of rubber from the insides of the PS hoses. This probably harmed the bearing in my PS pump where the pulley is pressed on. And it would only have gotten worse. So I took care of it.

After my EVO delete, I have nice, fresh fluid that should stay that way for 20 more years. Sweet, sweet success !

But now, of course, the tires and struts need attention, from post #4. I would like to get both matters fixed before I drive (Louisville to Cincinnati) for the cancer survivors' dinner May 1. My bone marrow (Hodgkins) went back into my chest to reboot my immune system (hence the term "bone marrow transplant") 02-01-2005.

Yep, it's pretty much solved. All is good.

 

Congrats on the PS remedy.
Also, congrats on beating cancer and being alive.
I have a BIL with leukemia. His blasts are undetectable right now, but he wake6d into the doctor's office with stage
4 leukemia. The fight is never over.

For struts, go with the KYBs all around. Rear is same as stock, fronts are a bit stiffer than stock, but they are solid quality and they last.. I replaced mine when I couldn't stand the ride. That was about 180k. Someone reasonable prob would do every 60k. Be sure to get KYB mounting hw for the fronts. The bearings will likely come apart and empty onto the floor. The rear mounts have the bump stop incorporated. Up to you if they get replaced.
Fun job inside the car up against the base of the rear window
Should be able to use mid length sockets. Or maybe offset wrenches since the strut "tower" is raised. Haven't done in a while.

I had hankooks on my SC2 for any years. Capable all around tire with good tread wear.