My last cry for help, engine shaking when steering

[alekseykorzun]

I have 540I/6, when car is stationary, below 400RPM and wheel is turned it 'bites' makes a noise and I can visible see engine shake at the same moment that happens.

New pulleys, new junked steering pump, fluid drained replaced, no leaks on pump level, proper fluid, new tensioners, new belt.. tried shorter belt... etc.

I don't know what to do next...

[floydr]

I wonder if one of them is broken.

[alekseykorzun]

Engine mounts are brand new, and would the engine shake all the time .vs steering at idle? If I give RPM and turn the wheel it's fine.

[KSKarl]

Check the idle speed controller. the load of working the steering at idle is slowing the engine enough to get into an rpm that shakes.

[alekseykorzun]

Is that basically TPS sensor? I replaced it it's pretty much new (1 month).

[KSKarl]

..or whatever BMW calls it. It's a computer controlled valve that regulates the idle speed. Computer drives it open or shut to maintain the specified idle rpm. It should be just below the throttle.

[alekseykorzun]

That was replaced and cleaned with carb cleaner, my MAF is brand new too... I'm going crazy.

[bonzo]

It could be the belt alignment of the pump pully in relation to the rest of the pullies under load when turning the wheel at low rpms. Did this problem start after replaceing the old pump and did the replacement pump come with the pully or did a new pully have to be pressed on?

[alekseykorzun]

Hi, I replaced the pump 2 times each time it had it's own pulley and now I'm running secondary pump with a brand new pulley that I ordered.

Define pressed on? You mean if it's bolted on tight to the actual pump? If so the answer is yes.

Thank you.