Intermittent loss of steering. Scary!! please help.

[gswede]

The last few months I`ve been having steering issues. When cold I have trouble engaging steering to the left, like the steering rack has to overcome a “nudge”.
When the car warms up, (which now takes about 30 minutes or so, and only under load. Changed the thermostat twice since October with no positive result – ongoing investigation) the steering operates as per normal.

The “nudge” feels more like a fluid pressure issue rather than mechanical.
Let’s say I`m going in a straight line and want to turn ever so slightly to the left, it feels like there is pressure holding the steering back, just for a second or so. During this second, no amount of force applied to the steering wheel can overcome the pressure. Meaning that no matter how hard I turn the wheel it wont pass midpoint to start turning left

I have heard of XC90`s having trouble with their steering rack o-rings. When bad, the steering servo pressure nullifies steering wheel input, as there is the same fluid pressure on both sides of rack.
According to Volvo, they have never heard of this issue on our s40/v50.

I have had the mrs leave the car at the dealers. One of the mechanics will have the car for two weeks as I am off for overseas work. As he is addressing the thermostat issue he is taking the car home after work to more thoroughly diagnose thermostat, seeing how the the engine heats up from dead cold. Happily he does this on his own time, not charging me.

Well, this morning I talked to him and sure enough. The steering did this thing a few times on his way to work. He mentioned the rack issue on other Volvos and proceeded to tell me that a new rack, if indeed it is the root cause, will be 4000USD for the part alone, then labor on top of that.

Have any of you guys experienced the same? Does anybody know how such a st-rack problem would develop?
I remember from my muscle car days the whenever I turned the wheel all the way to one side, the servopump/rack would start squealing as if it was bleeding pressure like crazy.
Guess I`m asking if holding the wheel locked all the way to either side could result in o-rings bursting or whatnot.

Any feedback will be much appreciated.
This car is really beginning to get to my nerves,
Some data, 2004,5 v50 T5 GT 60k miles.

Almost forgot to mention, the problem goes away when the car reaches operating temperature.
Is the steering fluid heated by loop through engine or engine coolant by any chance?

Could it be that the fluid need changing, thinking if it was the o-ring in the st-rack it would be the same problem regardless of temperature.

BTW, steering fluid reservoir is at normal level. Fluid color is dark brownish, no particular burnt smell.

[ian7675]

$4000 Really? Surely that a 0 too many.

[Daim]

I think it is more so, that the steering position sensor is either broken or damaged. Iirc the P1 Volvos have an electro-hydraulic steering system (not all) which only activates the power steering pump, when the wheel is turned...

[gswede]

Got word from dealer mechanic today. They suspect it could be a misalignment or otherwise a suspension problem. Given that the problem only occurs while at speed. When stationary everything feels normal.

Not holding my breath but crossing my limps..:-)
Hopefully I will know more tomorrow.