[pacificbyte]

Searched the forums and didn't find a thread with my symptoms, so throwing this out there:

97 528i: >229,000 miles
production date: 11/96

-Rack and pinion was making noises at 228,500 miles. changed the PS resevior hoses (supply and return), and flushed fluids.
-Changed the rack and pinion (new Atlantic Enterprises unit)at 229,000 miles as well as the power steering pump (LUK reman).
-Pulleys and belts were changed ~225,000 miles

symptoms: :violent: involuntary steering from 11:00 to 1:00 position while I was at a standstill in a driveway. At one point, the steering locked up when I restarted the car. no visible problems at the PS pump, resevior or under the car. After a few minutes of turning the motor on/off, I was able to have somewhat of manual steering. More force was required compared to tryning to turn the wheels with the engine off.

with the front end on jackstands, I'm able to get somewhat of smooth turning to the left, but the system feels like its bindind turning to the right.

There's fluid going to the pump from the resevior, so I've eliminated the resevior filter.

I wasn't able to get the M14 banjo bolt off at the rack and pinion to check the supply line from the pump, but I was ble to disconnect it at the pump. there's fluid in the line.

I believe I've elimiated the PS Pump, and it's the rack and pinion, but wanted to see if anyone has experienced a similar problem, and what their fix was.

Other than what i've checked, could there be any other parts which could effect the system to react this way?

Thanks in advance!

 

[granlund]

I had somewhat similar symptoms as yours with the steering almost locking up at certain angles. After replacing the strut top mounts, which had badly worn out bearings, problem was gone.

 

[MatWiz]

What is "involuntary steering"? Can you instead describe what it is?

You've changed the rack and pinion at 229,000 and now you have >229,000 on the car??? What does THAT mean?

Who is Atlantic Enterprise? Do you have a link? And what exactly did you buy? Brand new? Fixed unit? How much did you pay? You are suspecting them to have sold you a defective unit, right?

Did you DIY it, or did you give it to a shop, to change the rack?

mw

 

[pacificbyte]

I had somewhat similar symptoms as yours with the steering almost locking up at certain angles. After replacing the strut top mounts, which had badly worn out bearings, problem was gone.

thanks for the input Granlund. I had replaced the strut tower bearings at ~192,000 miles. They stilll appear to be in good condition.

 

[cn90]

At that mileage and with that symptom, change the PS Reservoir and see how it goes.

The PS Reservoir is cheap, about $25.

 

[pacificbyte]

What is "involuntary steering"? Can you instead describe what it is?

You've changed the rack and pinion at 229,000 and now you have >229,000 on the car??? What does THAT mean?

Who is Atlantic Enterprise? Do you have a link? And what exactly did you buy? Brand new? Fixed unit? How much did you pay? You are suspecting them to have sold you a defective unit, right?

Did you DIY it, or did you give it to a shop, to change the rack?

mw

MW,

'Involuntary' would mean that the steering acted on it's own. As I was about to turn right out of a parking lot driveway (from a stop), the steering wheel began to repeatedly move from left to right. The amount of movement would mirror a clock from the 1:00 position to the 11:00 position (counter-clockwise to clockwise to counter-clockwise). The action was very abrupt, as I was not able to grip the wheel to stop it. I had to shut the engine off. At one point, the steering did lock up, but it now operates in what I would describe as worse than manual steering.

Regarding the mileage, I was able to drive on the new rack and pump for just under 400 miles before the steering system failed. I changed the rack and pinion, and the pump at 229,025 miles. It failed at 229,418 miles.

I purchased the Atlantic Enterprises rack and pinion as a new unit (ManfPart# 3210/N, $484.00) from bimmerspecialist.com, along with the remanufactured LUK PS Pump (ManfPart# 5410077100, $380.00). Atlantic Enterprises assembles new rack and pinions out of North Carolina (http://www.atlantic-ent.com/rack-pinion.html) Cost was a factor which is why I chose their rack and pinion, as it was a fraction of the cost compared to a ZF Sachs, remanufactured part which required a core exchange.

The install was done with the help of some friends. One who has been a long time, certified BMW mechanic, and performed the work. The other, who owns an auto shop that provided access to his lift and tools.

My intent is to narrow the part that is causing the steering problems. I opened a RMA ticket with Bimmerspecialist, who promptly returned my emails and called me to try and trouble shoot. A+ to them for their response, and willingness to resolve the problem. I'm reching out to the forum community to tap into other peoples experiences. At that point, I hope to be able to pull the correct part for an exchange, or possibly identify another part of the steering system that I might be overlooking.

 

[granlund]

MW,

'Involuntary' would mean that the steering acted on it's own. As I was about to turn right out of a parking lot driveway (from a stop), the steering wheel began to repeatedly move from left to right. The amount of movement would mirror a clock from the 1:00 position to the 11:00 position (counter-clockwise to clockwise to counter-clockwise). The action was very abrupt, as I was not able to grip the wheel to stop it. I had to shut the engine off. At one point, the steering did lock up, but it now operates in what I would describe as worse than manual steering.
...

Did the steering start turning to one side while car was completely stopped? If so, I have no other explanation than that there is something wrong with the rack.

Try starting the car with the front wheels jacked up. If the wheels at any point turn in either direction, the spool (rack) is bad.

 

[MatWiz]

MW,

'Involuntary' would mean that the steering acted on it's own. As I was about to turn right out of a parking lot driveway (from a stop), the steering wheel began to repeatedly move from left to right. The amount of movement would mirror a clock from the 1:00 position to the 11:00 position (counter-clockwise to clockwise to counter-clockwise). The action was very abrupt, as I was not able to grip the wheel to stop it. I had to shut the engine off. At one point, the steering did lock up, but it now operates in what I would describe as worse than manual steering.

The steering wheel is moving by itself, when the car is not moving??

Sounds like the servo is going haywire maybe? Do you have the servotronic type steering rack? There are two types, one with servo one without.

Servo engine is a kind of engine that "knows" when to "stop" at a specific position - based on the input it receives. My logic is that if it moves back and forth (left/right), then it is "fishing" for the right position, but cannot get itself to "zero" between the input and the output. Sorry if it doesn't make sense.

I'm just throwing out possible scenarios that maybe will lead you to the solution.

mw

 

[granlund]

...Do you have the servotronic type steering rack? There are two types, one with servo one without.
...

Was Servotronic really available on E39s built 11/96?

 

[MatWiz]

Was Servotronic really available on E39s built 11/96?

I don't know. I rather ask him instead of doing a research for him. I am not a walking parts catalog, you know.

mw

 

[pacificbyte]

I don't know. I rather ask him instead of doing a research for him. I am not a walking parts catalog, you know.

mw

non-servtronic. I beleive servtronic was produced some timein 1999.

The steering wheel started moving on it's own when I started letting off of the brakes at a standstill.

I checked the resevior to confirm that there's flow both ways. I also confired fluid in the both supply, and high pressure side of the pump. I then disconnected the tie rods to isolate the rack. I still get a ton of noise turning the wheel to the right.

I'm pretty sure it's the rack n pinion gone bad. replacement should be here tomorrow.

Thanks everyone for the tips.

 

[granlund]

Yes, I concur. Definitely a bad rack. Probably a worn out spool on the input shaft that leaks fluid to one port.