Drivetrain vibration.

[DanielHStout]

I swapped a good m20 motor and tranny into my 86 325es a while back but I still have a few small quirks. The one that bothers me the most is a slight but noticeable vibration somwhere in the drivetrain. I only really notice it when accelerating fairly hard in first or deccelerating in first gear. I was thinkimg maybe the guibo is misalligned or something like that, or maybe the driveshaft bearing is faulty. Anybody have any other ideas? Also the car seems to have a kind of pulse in power on acceleration and it kind of seems like it is running a little rich. I changed the O2 sensor but it didn't seem to help. Any ideas on this?
Thanks for any input.

[lordofthewaters]

Check your driveshaft support bearing, and your fuel filter. Those woul be my first guesses.

[HST]

If you took your driveshaft apart and back together, it is most likely out of balance.

[Garageaholic]

To add to the driveshaft problem...

You must put the driveshaft back together on the same exact splines that it was on before you took it apart... the U-joints are balanced to work only in that orientation. That could be a cause. There may or may not be little white marks on the driveshaft showing you which orientation so properly re-install the driveshaft

[HST]

To add to the driveshaft problem...

You must put the driveshaft back together on the same exact splines that it was on before you took it apart... the U-joints are balanced to work only in that orientation. That could be a cause. There may or may not be little white marks on the driveshaft showing you which orientation so properly re-install the driveshaft

What I ment to say ;)

[DanielHStout]

I didn't take the driveshaft apart i just disconnected it at the guibo. How would a fuel filter effect any of this?

[Mike325]

I didn't take the driveshaft apart i just disconnected it at the guibo. How would a fuel filter effect any of this?

The part about it running like it is rich. Could be a bad filter.

[lordofthewaters]

Yes, What he said. I didn't specify which symptoms I was addressing.

[ummagawd]

i have this drivetrain vibration too... its annoying as all hell

[Garageaholic]

Then check your wheels being balanced. that is a simple culprit..

[ummagawd]

wheels and tires are new (for me dunno about the OP)

i only get it at certain speeds under acceleration... at around 80-85 my car feels like its about to fall apart

[lordofthewaters]

Warped rotors?