Sudden, complete loss of power steering

[TTManUK]

I am not having much luck with my car at the moment. Having just got it back on the road after a failed MOT and prior to that, a failed wheel bearing, I was driving earlier today, around an hour into the drive, and all of a sudden I get a brief whining noise and then complete loss of all power steering. I managed to limp along to a turn off, I could barely wrestle the car round the corner. It was raining at the time, so I could not check for obvious fluid loss, but does anyone have any inclination as to what this may be? Car is a w204 C63, I assume PS pump or serpentine belt, but am hoping that it could be something as simple as a split or disconnected hose. What has confused me, is that I didn't get any lights or errors on the dash to indicate there was any issue, which I assume would be expected in the event of such a major failure? A cursory Google search shows a fair amount of failures in the US, but usually as a result of them doing burnouts/doughnuts on full lock - I was driving completely normally, and don't tend to abuse the car in such a way.

As usual, the car has failed right at the worst time, so will not be looked at until at least Monday - so in the interim, has anyone else experienced something similar, and if so, what did the cause turn out to be? Thanks

 

[ChrisHGTV]

I had something similar a while back after driving through a puddle. Power returned after about 30 seconds driving and its been fine since. The learned collective on here thought water had got on the belt causing temporary slipping which makes sense. Has power still not returned on yours? The fact it was raining could point to water on the belt somehow?

 

[mm450exc]

Check the power steering reservoir.

I had this and mine was empty. No leak and good since then.

 

[TTManUK]

Thanks for the suggestions chaps. I had the car recovered, so I have no access to it now. Annoyingly I am away at the moment, I am staying in Cornwall, but the breakdown happened in Devon, so it has been recovered about an hour and a half away from where I am staying. No chance of me having a poke around, I did have a quick look at the belts (as much as is possible in that cramped engine bay in the rain) and could not see any obvious signs of belt damage, could be slipping though. I'd be equal parts relieved and embarrassed if it was as simple as a fluid level issue, however a) would that not throw an error on the dash stating as such and b) isn't it a closed system, so how would it be empty if there was no leak?

 

[Doodle]

Both times this happened to me, it's been loss of aux belt. S211 seized water pump shipped the belt off the front of the pulleys, R129 snapped the belt on kickdown as I joined the M4.

 

[DSM10000]

Check the power steering reservoir.

I had this and mine was empty. No leak and good since then.

If the reservoir is empty there must be a leak somewhere.

The fluid is in a sealed system.

 

[markjay]

As others said, fluid or belt.

Failure of the power steering pump itself is also a possibility, though it's less common.

Belts can snap, seize, slip, or freewheel (if a pulley bolt becomes lose).

 

[TTManUK]

Thanks gents. Does anyone happen to know if the belts are shared across the 204 platform, or will I need a C63 specific one? Wondering how long I might have to wait for a part in rural devon...

 

[markjay]

I can't imagine that the M156 engine will share any components with the M271/M274/OM651 etc.

 

[markjay]

On another note, assuming that the same belt also runs the alternator, the loss of steering wheel assistance would have likely brought up the charging warning on the dash.

 

[TTManUK]

I got no dash warnings whatsoever. In hindsight, I should have tried turning the AC on to see if that worked, to establish if it was belt related. Live and learn, hopefully it will get diagnosed tomorrow and I will report back

 

[TTManUK]

Got a call back from the garage who recovered it, apparently a hose has split - on first being told this news I thought oh good, a relatively cheap fix - £250 odd + VAT for the part (Merc only) and 12 day lead time from Germany, then 5-6 hours labour as it required the subframe being dropped to fit the pipe, so looking at £1000+. Seems a lot for a PS pipe, however I have not done that level of work on this platform - does that labour estimate sound about right for that level of disassembly?

 

[ChrisHGTV]

Got a call back from the garage who recovered it, apparently a hose has split - on first being told this news I thought oh good, a relatively cheap fix - £250 odd + VAT for the part (Merc only) and 12 day lead time from Germany, then 5-6 hours labour as it required the subframe being dropped to fit the pipe, so looking at £1000+. Seems a lot for a PS pipe, however I have not done that level of work on this platform - does that labour estimate sound about right for that level of disassembly?

Ouch! What about someone like Pirtek hoses, could they make something up? I’m sure I’ve heard of someone on here using them before.

 

[TTManUK]

He explicitly said there is no 3rd party alternative, and off the back of my call I think made the order with Merc, so probably too late to go down that route unfortunately. Just had a quick look on the Merc EPC and I am struggling to see what PS hose could possibly be costing £300! Anyone more familiar care to offer an opinion as to whether I am being taken for a ride (not that there is much I can do), or if this is genuinely the most expensive piece of rubber in the world?!

 

[TTManUK]

So from further research it seems the part is the high pressure hose part number A2044600643, based on the few listings I can see for the part, the price seems about right. I am hopeful since it wasn't the belt, that nothing else was damaged in the failure and I did not knacker the pump running it dry

 

[markjay]

PAS hydraulic pumps are usually pretty simple and pretty robust devices.