3B steering stiff after some spirited driving

[gmac78]

Evening All,

I have a problem with the power steering on my 3B where it will be working fine with no issues, nice and light at slow speeds like it should be, then if i go out for a good thrash, more times than not when i return home the steering feels stiff to turn at low speeds. Switching the car off and back on returns it to normal light steering.

The rack doesn't grumble in anyway, i've not noticed any leaks, doesn't go through fluid etc.

Any ideas what could be causing this?

Cheers

[mike74]

Overheated steering fluid maybe, what colour is it?

[SteveH]

As mentioned, overheating the PAS fluid will create heavy steering. Is the problem fixed instantly when you switch the car off and back on, or do you leave it to cool down? If it's instantaneous, it's likely to be something to do with the servotronic valve in the rack or its controller. You could do a test by disconnecting the servotronic controller, located under the rear seat. If this produces the same feel to the steering it's something to do with that circuit.

[gmac78]

Overheated steering fluid maybe, what colour is it?

I changed the fluid a few years back, not done much mileage since then. Offshore at the moment but will check when i get home.

[gmac78]

As mentioned, overheating the PAS fluid will create heavy steering. Is the problem fixed instantly when you switch the car off and back on, or do you leave it to cool down? If it's instantaneous, it's likely to be something to do with the servotronic valve in the rack or its controller. You could do a test by disconnecting the servotronic controller, located under the rear seat. If this produces the same feel to the steering it's something to do with that circuit.

Yeh switching the car off and back on seems to do the trick, didn't know that the controller was under the rear seat, good call, i'll have a play with that and see if it feels the same when disconnected. Is there much to the valve itself on the rack? I take it it's not a serviceable item?

Cheers

[andy10v]

Sounds like the servotronic as Steve says, it should be lighter at lower speed, heavier at higher speed. If you unplug the servotronic ecu under the rear seat it will be "heavy" all the time.

Wiring

http://www.s2-audi.co.uk/workshop/schematics/servo/servotronic.htm

[SteveH]

As a note, the ABY didn't have a servotronic rack, so the 'heavy' steering will be the same as what's standard on a later car. Could be the electronics or the servotronic valve in the rack not functioning correctly.