e34 hesitating

[madman525i]

I have a e34 525i Wagon. I am having a hesitation problem. When I accelerate the motor shakes real bad and I have lose of power. the motor runs good until it reaches normal operating temperature on the gauge. The motor idles good. if you rev the motor slowly it is okay but if you rev the motor fast it will hesitate and shake. No codes and no check engine light. I have changed plugs, gas filter, cam sensor, crank sensor, Mas air flow sensor, temp sensor, checked fuel pressure. I changed all of the vacuum lines. I changed O2 sensor, throttle position sensor.
Any Ideas on how to fix.

[JhwShark]

You have done a lot of the stuff for the electronics system/sensors and vacuum integrity. So soon time to examine engine condition. How many miles on it?

What are the conditions that occurred when this started...driving uphill accelerating or downhill no load under backpressure, cornering under deceleration??? Specifically what happened when you first noticed this? reving while driving or in the driveway?

Have you adjusted the valves?
Is it fuel starved under high speed accel? fuel pressure regulator.
What is the compression? If one cylinder is lower squirt oil and recheck if improved than possible ring.
Jon

[madman525i]

Well, when I first noticed it is when I was excelling to get on to the freeway. I could feel something, just a little bit of a hesitation. Then it just keep getting worse and worse. I brought it to a mechanic that said he did not know what it was. No codes or check engine light on. I will check the compression and what else should I do. I have 175,000 miles. I never did any mechanical work to the motor.

[JhwShark]

Sometimes the "mechanics" don't think beyond a computer code...
Under load your rig has some performance issues; with your mileage you may have some worn valve guides, seats, valves and would benefit from a valve job. Hopefully nothing in the block (rings) to deal with

However, do the compression check. At this mileage it will give a perspective on engine condition and any next steps. It is also a low cost high yield analysis tool.
Jon