power steering problem
 

hello,

I have a problem with my power steerign of my x300 xjr6; when the engine is cold the power steering works well and easy but when the car warms up the power steering is very hard. fluid level is FULL.

Steffen

RE: power steering problem
 

As a guess, perhaps the p/s pump is getting weak. Maybe as the fluid heats and thins, the pump is weak and having trouble pushing it??? Just a guess. I can't really think of any other plausible reasons...and this seems kind of a goofy guess.

RE: power steering problem
 

The reason for hardening of steering as the fluid heat goes up is due to the rack and pinion and fluid cooling condition. Try also changing the whole fluid including those inside the rack with a higher grade power steering fluid.

RE: power steering problem
 

Couldn't hurt to replace the fluid and bleed the system. The correct flluid is Dexron III....not sure what Cool had in mind for an upgrade.

There's always the posibility of an electrical malfunction. The steering control module takes a vehicle speed reading from the instrument cluster (which gets its reading from the left rear wheel sensor) and adjusts the assist according the road speed. Maybe, just maybe, you have a module problem? <shrug> Sometimes solid state module act up when they get warm.

Not much help, I know.

If you have a shop manual I'm sure there are some circuit tests ......

Sorry
DD

RE: power steering problem
 

If in case it is indeed steering speed control module it is located on the lower A pillar left driver side (US) take out the plastic cover and you will see and have a full access to the servo module which controls the stiffness due to speed reading. You can try to test it by using an ohm meter to see if the reading kicks up every time you turn the steering even at a stand still, another possibility is you might have to purge the system if in case you have opened up the system before.

by the way when i mention upgrade of fluid i meant changing it if it was not the correct grade.

I have the same problem with xj6 sovereign. The service guy thought that it was the pump. We changed the pump with a refurbished one. Same problem. We thought that it was "not good refurbished". Bought an original pump. Changed the cooler. Again the same. :icon_doh: We opened the pumps and saw that the valve was stuck in all of them. Cleaned the brand new one. Put it on "another" car. Again the same. :icon_doh: In two minutes no power steering. Yes the fluid heats. Valves in the pumps stuck. We don't know why??? And something causes the pumps to fail. I'm afraid I've lost two new steering pumps. Steffen did you solve the problem? Please urgent help..

Hello cemreis,

I have still the same problem, when the car is cold, the power steering works fine, but after a couple of minutes, the power steering works very hard.
I've changed the whole fluid with dexron 3 and still the same problem.
The question is, how can i kwow if it's the power steering pump, or the steering box/rack?

Many thanks

Steffen

There is a valve inside the pump. When the fluid heats the valve stucks and power steering fails. The repairman opens the pump fixes the valve but in 2-3 minutes it stucks again because of the heat. Mow they're trying (since 1 week) to find the cause of the over-heating. We checked everything, box, cooling device. No reasons yet. If we find out something I'll inform you.

thanky you!

i Noticed, when the power steering goed very hard when the engine is warm, that when i push the accelator a little bit (around 1500 rpm) that the power steering works a litlle bit more easier, but not 100%
Where is that valve located, where you talked about?

Steffen

Bad pump, Cool is right about testing and eliminating the servotronic assist as a possible cause. Disabling it doesn't make the kind of change to steering effort you are talking about.

A bad rebuilt pump causes the same symptoms as a bad pump. A good pump will fix the car.