Power steering Q...

[Calypso]

I've got a 93 MTX. When I start the car in the morning, the power steering works fine, but after it heats up for a few minutes, it doesn't work unless I rev the engine (or am driving). Now, I was wondering; could the power steering fluid cooler be the culprit? I know I've seen that thing in the engine bay, and it doesn't look pretty. Just found out that it is the power steering fluid cooler, and thought that may be a good thing to check. Power steering fluid is full, too. If it's not the cooler, I have no idea what it is.

Thanks...

 

[FoeSho]

If it changes with temperature, I woudl have to say its either the pump going bad, or the rack seals.

 

[SHOtimer]

What is the color/condition of the fluid? A fluid flush might help you a great deal if you have the original fluid. Other than that - your pump or rack is culprit. I had a similar problem with my SHO when I got it ~130k. I flushed my fluid and kept it fresh, this helped a lot. Then I finally replaced my rack when I swapped my motor - that made the world of difference.

You might also have a problem with the VAPS module.

I would start with the fluid first, because it is cheapest/easiest. And old fluid doesn't hold up very well once it gets hot - which is your problem.

Doug

 

[white93atx]

vaps

What does the steering act like when the vaps goes bad ? Just put new rack in my car,much better. It was leaking very badly.

 

[SHOtimer]

Well, the steering assist can go out completely, or default into one mode all the time....or just be inconsistent (outside of it normal characteristics). I too noticed a huge difference with a new rack - the old one had 165k on it.

Doug

 

[the_jase_case]

Bringing back an old thread, this is my current car, the one that was originally mentioned by Calypso. And I am still having the problem after a fluid flush. The fluid was Black, and it is now a dark transparent color, I know it should be clear.

Ok, he also mentioned that it might be the PS temp cooler. Does anyone know how much these cost? Also is there any type of diagnostic that I can do to the car to figure out if it is either the cooler, pump, rack, or (hopefully not) all three?

Oh, symptoms are still the same. Except that steering can be knotchy while driving down the road in a straight line.

 

[itwonder]

One other simple check, make sure the belt is tight. There is little to go wrong with the cooler other than if it springs a leak. The pumps seldom fail other than springing a leak at the shaft seal. Even with a good flush, it's difficult to get the fluid to run clear on an old rack.

 

[SuperHO]

meh, just swap out to a gen III subframe with that nice, smooth ZF rack....

 

[the_jase_case]

meh, just swap out to a gen III subframe with that nice, smooth ZF rack....

This is actually what I would love to do. If I find out that it is the rack, I may just end up doing this. Maybe a next year project.

 

[93rev2sev]

Jasecase,

I have more than a little (and recent) SHO PS experience.

If you have VAPS and you have inconsistent steering effort, the VAPS can be unplugged very easily. If the VAPS unit was your problem, your steering effort will become more consistent and the effort to steer will be lighter.

An other reason for your symptoms might be subframe alignment or deteriorated bushings. Ususally, though, the symptoms from this will feel like the rack is sticking on lane changes(which you mentioned). In my case(with all 3 cars) the off center sticking was subframe bushing deterioration and subsequent poor subframe alignment.

I CAN tell you that the cooler is most likely NOT your problem. Nor is the pump.

I will almost gaurantee you that the biggest problem with your steering will be the subframe bushings and or subframe alignment.

It's easy to check if you have a jack and jackstands(you can check it with just a jack, but not as easily)...

Here's how...

Jack up the car high enough that you can put a jackstand under the subframe on the right rear corner(do the other rear corner the same way). It's important that the jack NOT be under the subframe, but just behind the mounting point on the unibody frame rail. As you(carefully) lower the vehicle on to the jackstand, make sure it's securely centered under the corner of the subframe and note how much the subframe to body "gap" changes. I have a feeling that you will be ordering new bushings and recall kits right away.

 

[the_jase_case]

My subframe bushings were actually just replaced in May of this year just before I bought the car. If it is VAPS how do I turn that off? I just want to check to see what difference this would make.

 

[93rev2sev]

Jack and support car in front(jackstands on corners of subframe near the strut rod receivers). Remove drivers wheel. With a penlight, identify the rack and associated electrial connectors(2 of them). Crawl under there(head under oil pan, feet under shifter). Disconnect them and zip tie them out of the way. Replace wheel, lower vehicle...enjoy "full boost" power steering at speed.