losing power steering under acceleration

I can definitely tell you that the alignment had nothing to do with the problem...but it does drive straight now. They suggested looking into the pressure relief valve, but went with the replace till fixed method.

I just went out and cleared out the gear and the hose...the hose was completely clear with no obstructions and blowing high pressure air in both directions had no adverse reaction. Without taking the gear out and tearing it apart I can only assume it is clear after removing all the fluids. Still have the same problem so I'm pretty sure it is in the pressure valve and will do this all again this weekend when the new pump arrives. Nice thing is I found one with the housing so I will have a spare housing as well.

At idle, no trouble...around 3K my steering either locks entirely or at least wont return unless I let off the gas...then its normal. Sounds like the valve is opening when it shouldnt be.
 
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Wait a min wait a min........my steering LOCKS...meaning I cannot move the wheel at all...its stuck until I let off the gas.....If im not mistaken, when your pump fails for whatever reason you should still be able to turn the wheel because there is a mechanical connection inside the gearbox that is simply "assisted" with the piston.....if my wheel is totally frozen then wouldnt that point to a failure in the gear box or the control valve on it? Maintaining equal pressure on both sides of the piston keeping me from moving it at all? See where Im going with this? Something with the reaction springs and the pressure behind them...
 
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Wait a min wait a min........my steering LOCKS...meaning I cannot move the wheel at all...its stuck until I let off the gas.....If im not mistaken, when your pump fails for whatever reason you should still be able to turn the wheel because there is a mechanical connection inside the gearbox that is simply "assisted" with the piston.....if my wheel is totally frozen then wouldnt that point to a failure in the gear box or the control valve on it? Maintaining equal pressure on both sides of the piston keeping me from moving it at all? See where Im going with this? Something with the reaction springs and the pressure behind them...

You should be able to steer, just not as easy.

Here's my WAG. I'd start by looking at the motor mounts and see if the engine is rocking up against the linkage or column.
 
I also replaced the return fitting on the gear box...cant remember what its called...angled aluminum thing...

can anyone tell me about the return fitting with the check valve in it.....I dont know how it functions or what its purpose is. I replaced it, but new doesnt always mean correct.

Did you mark the exact position of this price before you took it off? It has to be exact, there is adjustment in it. I think this may be your problem. Alot of modern alignment shops won't know of this procedure. You can check it yourself with the front wheels in the air. Loosen the valve and center it, it moves side to side, hand tighten, start car with HANDS OFF! And no arms through the steering wheel! It may kick! Tap valve lightly to one side or the other until it feels good, tighten up, try it out! There's a more in depth thread on this procedure somewhere on this site, but that's the gist of it.
 
I don't know dude????? I can't figure out what's up with this???????? I'll be chewin popcorn on the sidelines worrying about other fish to stay healthy????? Good Luck
 
Did you mark the exact position of this price before you took it off? It has to be exact, there is adjustment in it. I think this may be your problem. Alot of modern alignment shops won't know of this procedure. You can check it yourself with the front wheels in the air. Loosen the valve and center it, it moves side to side, hand tighten, start car with HANDS OFF! And no arms through the steering wheel! It may kick! Tap valve lightly to one side or the other until it feels good, tighten up, try it out! There's a more in depth thread on this procedure somewhere on this site, but that's the gist of it.
Setting that was done by the book and I have no wander in it...I did score it before removing it.
 
I will replace the pump this weekend and see if that does it..if not then the gear is coming out.
That's all good, but you said
my steering LOCKS...meaning I cannot move the wheel at all...its stuck until I let off the gas

Something is really screwy here. Unless there's something I don't know about, there's no way the pump would do this. Why don't you jack the front of the car up and see what happens to test it. Take the belt off and see if there's a difference.

@3C's & a D? may be on to the problem, I don't know.
 
Something is really screwy here. Unless there's something I don't know about, there's no way the pump would do this. Why don't you jack the front of the car up and see what happens to test it. Take the belt off and see if there's a difference.

On a 94 Caravan that I had replaced the PS pump. After about 2 years and making a hard left turn to the lock, coming out of the turn, my PS went hard as if I didn't have any. I drove to 4 more stops like that, the went home w/no PS and the next day all was fine and hasn't happened again. Knock on wood! This was last year that this happened. It's got to be something in that valve?
 
Did you mark the exact position of this price before you took it off? It has to be exact, there is adjustment in it. I think this may be your problem. Alot of modern alignment shops won't know of this procedure. You can check it yourself with the front wheels in the air. Loosen the valve and center it, it moves side to side, hand tighten, start car with HANDS OFF! And no arms through the steering wheel! It may kick! Tap valve lightly to one side or the other until it feels good, tighten up, try it out! There's a more in depth thread on this procedure somewhere on this site, but that's the gist of it.

I have felt all along that this valve adjustment is your problem. When the valve is mis-adjusted, it causes the exact problem(s) you are having. It is a very tricky adjustment, and even some rebuilders don't do it right.
 
I have felt all along that this valve adjustment is your problem. When the valve is mis-adjusted, it causes the exact problem(s) you are having. It is a very tricky adjustment, and even some rebuilders don't do it right.
My only issue with this is that it happened out of the blue before I ever did anything to the steering. Rebuilding the pump was my thought for correcting the issue originally. It worked fine...then just one day it didn't. I wondering if there is a burr on the relief plunger or maybe the control plunger...or maybe a cracked reaction piston seal.
 
My only issue with this is that it happened out of the blue before I ever did anything to the steering. Rebuilding the pump was my thought for correcting the issue originally. It worked fine...then just one day it didn't. I wondering if there is a burr on the relief plunger or maybe the control plunger...or maybe a cracked reaction piston seal.

Well. . . The adjustment may have been fubar when you originally bought the car. Vexing problem. . .
 
Question....I know I changed all the fluids when I put the engine back in...including the PS....could I be using the wrong kind and that be the cause?

Just trying to think back about anything that changed prior to the issue.
 
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On a 94 Caravan that I had replaced the PS pump. After about 2 years and making a hard left turn to the lock, coming out of the turn, my PS went hard as if I didn't have any. I drove to 4 more stops like that, the went home w/no PS and the next day all was fine and hasn't happened again. Knock on wood! This was last year that this happened. It's got to be something in that valve?
But you still could steer. Read his quote again about how the steering locks up! No steer..

Plus, your Caravan had probably had rack and pinion.... Different animal.

I'm not saying that it's not the valve, I'm just thinking it can't be the pump.
 
Did you have the front end off the ground when the steering felt like locked at 3000rpm and above? As I have similar problems I think that I will do some testing with mine during weekend. Mine does not lockup but now when remembering the issue it sure feels much tougher to steer at high rpm while driving than it should even without the power assist. It can be turned but it feels rock heavy. As said before I have felt it only while counter steering during some not so legal driving maneuvers
 
I don't remember offhand about when it was off the ground. I think it did...but I know it does while driving and sitting in the driveway.
 
Question....I know I changed all the fluids when I put the engine back in...including the PS....could I be using the wrong kind and that be the cause?

Just trying to think back about anything that changed prior to the issue.

Nope. Definitely not a fluid issue. You said you used regular power steering fluid, and it's not foaming, so I'd say you're good with that. Get those wheels dangling!
 
OK...I jacked the car up and confirmed...the wheels do not wander on their own such as with the control valve being too far up or down, BUT there was a difference this time. under 2-3k the steering is normal...super light with no weight on the ground....hit the magic RPM and I lose power steering BUT I can still turn the wheel left and right, just heavy with zero assist, but not locked. Sounds to me like its the pressure valve in the pump. Confirm???
 
OK...I jacked the car up and confirmed...the wheels do not wander on their own such as with the control valve being too far up or down, BUT there was a difference this time. under 2-3k the steering is normal...super light with no weight on the ground....hit the magic RPM and I lose power steering BUT I can still turn the wheel left and right, just heavy with zero assist, but not locked. Sounds to me like its the pressure valve in the pump. Confirm???
Sounds like it’s the valve adjustment
 
OK...I jacked the car up and confirmed...the wheels do not wander on their own such as with the control valve being too far up or down, BUT there was a difference this time. under 2-3k the steering is normal...super light with no weight on the ground....hit the magic RPM and I lose power steering BUT I can still turn the wheel left and right, just heavy with zero assist, but not locked. Sounds to me like its the pressure valve in the pump. Confirm???
I think people are referring to the valve on the steering box.
 
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