Power steering died and resurrected. Twice.

[Sparky]

A few months ago my power steering quit after a single tight U turn. Figured I busted the pump. But then it started working normally again. Fluid was a little low so I thought maybe it got an airlock or something. It has been working normally until yesterday when my dad was borrowing the truck to tow a trailer. While he was maneuvering it around he made a tight turn and - you guessed it - the power steering quit a moment later. He shut it off for a few minutes while he went inside for something, came back out, started it up, and the power steering started working again after an initial heave on the wheel.

Obviously something is wrong, I just don't know exactly what. Is it the pump? Rack? Aliens?

Issues that I am aware of with my power steering (aside from it quitting twice):

1) Pump whines a little bit. It has ever since I got it 57K ago, and it isn't loud, but it is noticeable.
2) The lines are rusting.
3) The cooler evidently rusted through and the previous owner simply bypassed it by cutting the hoses off it and joining them together with double-ended barb fitting and hose clamps.

I was figuring on replacing the lines this spring and probably the pump. I technically should get a new power steering cooler also, but I'm not sure which one I should get (OEM is steel which seems junky to me) or how I should go about attaching the new hoses to an aftermarket cooler. I don't even know how the OEM hoses attach to the OEM cooler since all that was lopped off of mine by the previous owner.

Then I wondered if the rack itself may be to blame. Heck I don't know. That's why I'm asking the pros here for insight and opinions

 

[seanpooh]

I think the problem might lie with the pump since you're loosing pressure to actually turn at a low RPM when doing a U turn and tight turns. Also not having the fluid cooled at the proper temp isn't helping. My pump was being a brat after 159K miles only when turning into parking spots (tight turns at low RPM) and wheel locking. It worked in every other instance of wheel turning. I changed the pump and all went away.

I know there are the two lines on the driver side that leads to the cooler. I know for a facts that one goes from the cooler to the return basin of the pump. The other i believe goes from the rack to the cooler which is the high pressure side. Without a cooler your fluids must smell really burnt. Just remember the fluid is suppose to be clear or atleast close to clear.

Flushing the line might help but eventually the pump or something will need changed.

BTW, changing the pump is not all that hard. Changing the cooler out though, others might have some input.

 

[Sparky]

When the steering cut out engine RPM made no difference. And I've made tight turns before and after these incidents without it cutting out. That's the other weird part. It isn't really reproducible, it just does it when it feels like it (and in the most inopportune moment too). I still do suspect the pump also I guess, although I can't think of what would make such as simple device cut in and out like that.

The lines are what more concern me. The pump should be the "easy" part. But replacing those lines looks to be a pain Plus I'm not sure what part numbers I need. I know there is a high pressure pump to rack line but I'm seeing two styles on Rock Auto's site One has a metal portion in the center while the other is all rubber. Then there is the rack to cooler return line, then the cooler to pump line. Not the cheapest things either Looking at over $200 in parts for just the lines and pump. Each line except the cooler to pump line costs more than the pump does!

I know my cooler to pump line is rusting and I was just going to replace all the lines while I was at it, but maybe if the other(s) are OK I should just leave them alone and save the money and time/frustration of replacing them. I'll check them out well first of course.

 

[CaptainXL]

Just remember the fluid is suppose to be clear or atleast close to clear.

I am going to have to agree with this. A properly flushed system with no missing cooler should keep the fluid clear for quite a while. The reason I say this is because we have a 2011 Buick Regal and it now has 20K on it and I checked the fluid a couple weeks ago and it was still clear.

Obviously the OP needs some work done to the system. I would just start saving up to replace the lines and cooler and pump if you are planning to extend the life of the vehicle and plan on keeping it for years to come. Just make sure to thoroughly flush it BEFORE removing any parts so any new parts don't become contaminated or the whole exercise will be for not.

I would also check things like the belt tensioner, right sized belt and such. on a 2004 those should have been replaced anyway in the relatively recent past. But check them anyway.

 

[Sparky]

I'll be flushing everything with the old pump/lines in place before putting new stuff in, no doubt.

Thing is, I want it to be reliable but I am not planning on keeping this truck for years to come. It now has almost 170k miles on it and the body is rusting away on me. It simply just won't make it for several more years I don't think The plan is to get another Trailblazer to replace this one whenever that time comes, but in the meantime keep this one running as reliably as possible as cheap as possible.

Tensioner is good. Belt is only a couple years old and is good also. And I have an 02, not 04

No previous car of mine has ever had clear power steering fluid, they've all been brown All have been older cars with higher miles so I didn't know any better. I just thought that was the way it was. Oil is gold, ATF is red, gear oil is brown, brake fluid is clear, power steering fluid is evidently NOT supposed to be brown. Oops... This is the first vehicle I've ever had any power steering issues with anyway

 

[CaptainXL]

Tensioner is good.

Ok, so the tensioner has been replaced at some point in the past? I have 125K on my 05 and the tensioner was found to be shot when I replaced my idler and belt. Just sayin you might want to replace it if in doubt.

 

[Sparky]

I've not replaced it (just the pulley on the arm), but it shows no signs of being worn out. It is still in line with the rest of the pulleys, it isn't bouncing, the belt isn't slipping, and it is as stiff as ever to release it.

 

[CaptainXL]

I've not replaced it (just the pulley on the arm), but it shows no signs of being worn out. It is still in line with the rest of the pulleys, it isn't bouncing, the belt isn't slipping, and it is as stiff as ever to release it.

Alright, well if all of that checks out and the pump is working then I think there is a control valve which could be bad. This regulates fluid to either side of the piston in the rack.

 

[Sparky]

That would make sense. Is that in the pump? I seem to recall from another thread that I can't find something about a valve or fitting on the pump. Of course, the directions were to reuse the original valve if the replacement pump had a different size, so that wouldn't do me much good lol.

 

[CaptainXL]

That would make sense. Is that in the pump? I seem to recall from another thread that I can't find something about a valve or fitting on the pump. Of course, the directions were to reuse the original valve if the replacement pump had a different size, so that wouldn't do me much good lol.

The XL/EXT use the same pump but have larger size diameter orifices for the outlet side. I had to remove my fitting/orifice on the original factory pump and transfer it over to the new pump because it came with a SWB orifice.

I believe the reason for the larger outlet on the XL/EXT is to make up for or decrease fluid pressure due to the differences in power steering pulley diameter.

If that part was swapped over and your still having problems then it could be a problem with the rack. I am unsure where the relief valve is located but it could be on the pump inlet side or the rack. other than what I have said thusfar there really isn't much more I know about our power steering system but I hope this helps.

 

[Sparky]

I do appreciate it. I may just have to tear into it and just see what happens! I hope it isn't the rack