Bought a super cheap s70 with 286k miles on it, drove it 120 miles home with no issues, and have been driving it every now and then as a spare car

I was driving the other day and noticed very suddenly that I had lost power steering, on top of that, the wheel was completely locked, no matter how hard I pulled the wheel with both hands in either direction. I was headed toward the shoulder the way my wheel had locked up thankfully. I was then able to reverse the car into a nearby gas station by miracle of the angle my wheels were at, but by the time I had managed to park the car, the power steering was back.

Fast forward about 2 hours later, I'm going down the interstate in the right lane for about 3 miles, and when I'm getting prepared to take the upcoming exit, I notice my wheel is locked at 12 o clock, and only able to be moved to the left, unable to move past 12 o' clock to the right, I was panicking as I cruised for about half a mile in this state, again thankfully by miracle my wheels were angled perfectly with the angle of the highway and was able to safely get onto the shoulder and let the car behind me pass, by the time I was at a slow roll, the power steering had returned and I was able to safely drive for the rest of the way home.

I first checked the power steering fluid resevoir and at first glance it looked dark, thick and muddy. I flushed the system and the fluid was a very dark grey with a hint of brown, I also noticed that toward the end of the flush a clear liquid started to come out as well.

I replaced the fluid to begin diagnosing the problem, the car drove fine with no issue for 2 days, I even noticed that the steering wheel felt a lot lighter and easier to manuever, less strain on my hands/fingers etc. I was driving today and took a turn into a parking lot at a strip mall and I swear as I was turning into the parking lot the steering wheel felt sort of heavy I suppose, and before you know it I realize the steering wheel is locked, this time in a very awkward position as I sat there blocking several cars trying to leave this narrow strip mall. I sat there tugging on the wheel and moving forward and reverse in hopes something would happen but this time it took maybe 4-5 minutes until the power steering magically started working again and I could pull out. I was able to again drive for another 2 hours with no issues after that occurred.

My next guess was that if changing the fluid wasn't the trick the next thing to diagnose in the chain of command would be replacing the power steering pump? I figure maybe the issue occurs intermittedly as it does because the pump is getting clogged or jammed or whatever. The part isn't expensive and seems like a easy to reach fix.
I read when the power steering rack goes out it tends to leak fluid, I checked under my car overnight 2 different times, placed cardboard underneath and moved the wheel for several minutes but did not see anything leaking. There was also no visual sign of a leak near the hoses or outlet/inlets in the loop.

Another thing I want to point out is that when this occurs, I am completely unable to move the wheel whatsoever, which makes me wonder if it's actually an issue with the power steering, or could it rather be an issue with the suspension? Previous paperwork the last owner left me includes an inspection where a mechanic mentions something about tie rod ends in scribbled handwriting, and that makes me wonder if any part of the suspension could actually be the culprit? I think it's strange that the power steering will go out momentarily, and then magically comes back and drives like normal. I figure if it was something suspension related it would be all or nothing, and if something failed it would be a permanent thing.

Can anyone point me in the right direction with this issue? I figured I'd make a post before I take it to a shop for a diagnostic to know for sure what needs to be replaced. I've been googling this issue like crazy but there isn't a lot of helpful information

 

Lack of power steering does not make the steering wheel lock. For instance if you jack the front wheels off the ground - you can easily turn the steering wheel with the engine not running.

If your steering wheel does completely lock - as in can't be turned at all - you need to be looking at something mechanical - perhaps a bad ujoint in the steering column. I trust you are not removing the key while driving and engaging the steering column lock.

There are 2 flexible joints in your steering column.

 

I agree with Hoonk, it definitely sounds like something mechanical is jamming, as like was previously mentioned, you can turn the wheel without power steering, although it does require some effort. I'm curious though....next time it happens (although I wish it wouldn't), turn the car off and let it sit for a couple of minutes if possible. Then turn the key to "On" to unlock the wheel but not start the engine. See if you can move the wheel then. If not go ahead and re-start the car and see if that frees up the wheel. I'm just wondering if something in the steering rack is jamming under pressure from the power steering pump. Either way, I would not drive it much, if at all until you get it looked at......have it put up on a lift and check for any binding parts in the steering system. Please keep us posted on the outcome!

 

I'll probably take it to a shop later this week and return with any updates. I was definitely starting to lean toward the suspension being the issue which started to make me worry, and doesn't look like those parts will be easily attainable or cheap

 

Check out Rockauto.com You would be surprised how inexpensive and readily available most parts for that car are.......including steering and suspension parts.

 

Suspension parts are very cheap, but since you're having intermittent seizing of something in the system, I think the parts cannon is a very poor idea here.

I'm an engineer, and so I have opinions about this that are not just air, so to speak. here is what I think:
1. "loss of power steering" is not related to "locking the steering wheel". It's not the same thing. You have not experienced loss of power steering. If you lose power steering, you can still steer. You've really experienced loss of steering.
2. You could certainly have a ball joint that lacks lubrication (ball joints are cheap), but I don't see how that becomes intermittent very easily. it might. Fortunately, ball joints are pretty "inspectable". There's no weight on them in a volvo S70.
3. There is a mechanism provided in the car, by federal law, which locks the steering wheel on purpose. I don't think that is your problem, but you need to consider that very heavily. I've never had any trouble with it, but it's super-obvious that the steering wheel lock exists and you should have encountered it many times in your life on any car sold in the USA after 1969. No matter how sophisticated or new a car is (in my experience) it's still possible to bind up the steering lock when parked and you might have to help it out a little. On the S70, the lock engages when you pull the key out. That is an unusual way to operate it, but it works with less user input with manual transmissions. Volvo made a lot of them for Europe, so I expect that's why they did it. If any of this is new to you STOP and experiment with it. This is something that has been present on every car you've ever encountered and you need to be able to recognize it. I've never taken an S70 column apart to see how it's really actuated. I can't advise you there.
4. If I was going to gamble on something that could intermittently lock, I would have to pick the rack itself first, just out of desperation. The column is exposed, and the joint between the column and rack is exposed. You can see all that if you get a chance to look at it when it's locked.

Ultimately, it's going to be a difficult diagnosis, because you can't necessarily make it happen when you are able to get a mechanic to experiment with it. I had a car do this before, a long time ago. Was the rack in that case.