Power steering on a k11 how does it work?

NeX

You're after my robot bee
Club Member
hi all,

i was wondering if anyone could tell me exactly how the power steering on a k11 works.

i understand that there is an engine driven pump that pumps the fluid to the rack, then back out to a cooling pipe and then in to the resevoir and then down to the pump again..

there is no electronics except for a thing at the top next to the strut which i assumed was a solenoid that allows the fluid to flow round without going via the rack when the car is going at high speeds. but it looks like it is a sensor of some kind.

Does this mean that the micra power steering system is always on?
is there no way to regulate it to drop out at higher speeds?
what does the sensor report to? the ECU?

i have two micras with PAS and one is perfect and not too light, but the other is really light all the time, is there anything i can do to make it weaker?

thanks ppl
 
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NeX

NeX

You're after my robot bee
Club Member
the wheels will make a differance and also is its lowered etc, also the tracking could influence the steering.

the micra with the stiffer power steering (how i want it) has 13" super s alloys, fully pumped up, lowered 40mm and it is a uk 1.3Lx hardtop

the one with the very light steering has 15" ripspeed wheels on a 45 profile, not lowered, but is a 1.3 jap convertible...

problem is that the convertible already handles like a boat, it is very felxable, and with very sesitive steering it really doesn't help, it feels like it is always out of control.
 
what colour are the wires going to the 'thing' if they are B and G/B then it is the 'power steering oil pressure switch'

the black is GND, but the G/B comes strait from the ecu (pin 43). im not sure what the switch controls, but if you find out then please let me know because im not sure what to do with it when installing my hawk ecu:D.

hang on, i guess it just tells the ecu that there is enough pressure in the power steering fluid.
 
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NeX

NeX

You're after my robot bee
Club Member
what colour are the wires going to the 'thing' if they are B and G/B then it is the 'power steering oil pressure switch'

the black is GND, but the G/B comes strait from the ecu (pin 43). im not sure what the switch controls, but if you find out then please let me know because im not sure what to do with it when installing my hawk ecu:D.

hang on, i guess it just tells the ecu that there is enough pressure in the power steering fluid.

yea i am pretty sure thats what it is. but then what does the ecu do with that infomation? it cant increase the pressure if it is low because it doesn't interact with the PAS system at any other point. the best it could do is flash a fault code...
 

frank

Club Member
hi all,

i was wondering if anyone could tell me exactly how the power steering on a k11 works.

i understand that there is an engine driven pump that pumps the fluid to the rack, then back out to a cooling pipe and then in to the resevoir and then down to the pump again..

there is no electronics except for a thing at the top next to the strut which i assumed was a solenoid that allows the fluid to flow round without going via the rack when the car is going at high speeds. but it looks like it is a sensor of some kind.

Does this mean that the micra power steering system is always on?
is there no way to regulate it to drop out at higher speeds?
what does the sensor report to? the ECU?

i have two micras with PAS and one is perfect and not too light, but the other is really light all the time, is there anything i can do to make it weaker?

thanks ppl

nex, i think there is a valve around the shaft that sends equal pressure to both ends of the ram if the steering is straight, but if you turn the steering that valve will direct more pressure to one end of the ram (and less to the other end), so yes the p/a/s is working all the time, (tho not under load full all the time), you may be able to adjust the p/r/v, to lower the pressure
 

Antony

Ex. Club Member
ive never had power steering.... never been a problem, infact i drove a car the other day with power steering and it felt awefull, powersteering, abs and sloppy gearbox, fly-by-wire throttle and it was like driving porrige... sorry no.... being driven by porrige.
toyota yaris i think it was... eeeughk.... get a super S non pas rack..
 
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NeX

NeX

You're after my robot bee
Club Member
nex, i think there is a valve around the shaft that sends equal pressure to both ends of the ram if the steering is straight, but if you turn the steering that valve will direct more pressure to one end of the ram (and less to the other end), so yes the p/a/s is working all the time, (tho not under load full all the time), you may be able to adjust the p/r/v, to lower the pressure

ah ok, so it really is that basic, no regulator or anything it just runs all the time. thats fine, what do you mean P/R/V ? i am wondering if the Japs use a smaller PAS wheel on their pump and by fiting a uk pump i will be better off....

ive never had power steering.... never been a problem, infact i drove a car the other day with power steering and it felt awefull, powersteering, abs and sloppy gearbox, fly-by-wire throttle and it was like driving porrige... sorry no.... being driven by porrige.
toyota yaris i think it was... eeeughk.... get a super S non pas rack..

i know what you mean mate, i have lots of cars, some with PAS some without, and i feel more in control on the ones without, but i am not going to rip the PAS off my car, i just want to calm it down a bit.

i have been driving alot of hire cars for work (most recent was the latest Corsa) and they are ALL horrible! they are all cheap plastic clips with plastic covered engines and panzy stuff. worst one was the renault modis, and the best was the VW twin charged golf!

but its making me worried that when my little k11s finally die, there will be no decent cars left, just plastic toy cars....
 

frank

Club Member
nex, there,s sure to be a pressure relief valve, or else you would have little or no pressure on tickover and way too much pressure at high revs ( which is the opposite to what you want )
and i doubt if changing the pully size would help, for the same reason. and i would guess that the solenoid (at the top) is an ecu input for the idle control (ie, if you turn the steering while on tickover) :)
 
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NeX

NeX

You're after my robot bee
Club Member
nex, there,s sure to be a pressure relief valve, or else you would have little or no pressure on tickover and way too much pressure at high revs ( which is the opposite to what you want )
and i doubt if changing the pully size would help, for the same reason. and i would guess that the solenoid (at the top) is an ecu input for the idle control (ie, if you turn the steering while on tickover) :)

yea i see, it must be a mecanical relief valve in the pump itself.

and actually that kinda makes sense, the revs do pick up when i steer... but it doesn't explain why these two cars have a radically different feel, one is perfect, like no PAS but a little bit easier to turn the wheel and the other is so light it is imposible to tell if its aquaplaining or not...
 
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