clunking sound when turning

[theroundcow]

just re-did the front end of my e30. New tie rod end assemblies, struts, strut mounts, springs etc....so now when im driving and i begin to turn, it feels as if something inside the rack is resisting and then clunks into movement. At first i thought loose joint somewhere, doublechecked everything and found nothing. Then today i noticed it only does it when power steering is engaged, if i turn wheel with the car off the issue does not present itself. Its hard to look in the engine bay while turning the wheels but from what i can see when the clunking sound happens, i see my power steering hoses move quite alot. I once read that misalignment on the power steering system could cause this but im not sure which misalignment i should be looking for?

[roguetoaster]

Misalignment, I dunno, never heard that one, but does it happen continuously, or only in certain situations?

[theroundcow]

It seems to consistently happen when the power steering system engages. What is the ‘logic’ behind the e30 power steering system? When I turn the wheel what makes the pump engage and start assisting me with the turning motion?

[daveduck]

Did you make sure to put the washers under the strut mounts in? It's part number 31336776760 which is #8 here https://www.realoem.com/bmw/enUS/sho...diagId=31_0211. My first time putting new shocks in the front struts, I forgot to put these in, and it caused a clunking sound when turning which was because it was binding up since there was no washer.

[roguetoaster]

The pump operates continuously and changes output based on engine speed, pretty sure that side of the system is "dumb." In the rack there are a series of valves that allow a fixed rate, and presumably gradually increasing based on increasing angle, amount of flow and return. Pressure differential across the system, I assume at least, facilitates assist.

Check all of your PS line connections for loose clamps or leaks, make sure your PS level is correct and that the cap is actually sealing.

[theroundcow]

hey guys really appreciate the responses. i am relatively certain i have the washers where they belong but it certainly makes sense that a washer there could be binding, i did actually read a post about someone over torqueing their strut mounts so when they would turn they could see the strut mount deform when turning due to the binding motion. do you think i should be able to observe any deformation before the clunking occurs in my strut tower? the power steering system is definitely a weak point in this car, i never liked how expensive those dang hoses were. but could a pump be causing this issue? still very confused as to why it doesnt occur with power steering off, i guess the force input is occurring mostly in the steering wheel and the strut mount could deform differently when the power steering engages.

[theroundcow]

update here for anyone interested : lifted front end off the ground, wheels on, and again could only make the issue present itself with the engine/pump running. If the car was off there was no clunking to be heard/felt. We probed and probed looking for something loose while making issue present itself but couldnt not find any loose joints. I believe the issue is inside the steering rack. Going to look into converting to one of the e36 z3 racks and will let yall know!

[mike.bmw]

Check the sway bar brackets on the control arms. Mine did something similar and I spent forever tracking it down. Those U shaped brackets needed to be torqued to proper spec.

[theroundcow]

hm i will specifically go and check those but does it make sense that it would only occur when the power steering system is engaged?

[mike.bmw]

hm i will specifically go and check those but does it make sense that it would only occur when the power steering system is engaged?

As the power steering is applying forces to turn the wheels, loose suspension parts can shift causing a clunk. So, yes, it's possible turning the wheels can cause a clunk that's not internal to the steering rack or power steering pump. Hard to diagnose over the internet, but checking those U shaped sway bar brackets (at the point they connect to the control arm) should only take a minute. Torque both to spec. Rule it out and move onto the next potential cause if the clunk persists.