Vibration madness online.

[Bmwtvboy]

OK good points. First mpg on last couple of tanks is fine, the last highway was great. I don't notice any rattling or noise in general from the engine except the vibration issue. SO, I will start with changing the plugs to pure platinum. With the engine covers off I'll check the vacuum lines and spray carb spray around the intake area. I have owned this X since 38K miles and I have religiously changed syn oil and filter every 5Kmiles. I don't know if that has impact on longevity of Vanos or not. I also don't drive this very hard and fast. I hope it's just the plugs for now. Thanks again for all the support.

[Bmwtvboy]

Quick plug question. NGK, do not use a Bosch? And the NGK's will still be the four prong plug? Pure Platinum, no IR blends either?
Jeff

[racingbmwm3]

Search this NGK BKR6EQUP or this: 12129071003.
Or if you prefer Bosch: FGR7DQP or 12120141871. Bosch is cheaper, not sure if that actually means anything.

Also, when you go to clean your MAF, I recommend getting a tamper proof torx set and actually remove the sensor from the housing and spray the sensor directly. Can't really spray the sensor very well with it in the housing. Doesn't need to be wiped down at all, just sprayed.

[slowlanemcvane]

Originally Posted by racingbmwm3

Search this NGK BKR6EQUP or this: 12129071003.
Or if you prefer Bosch: FGR7DQP or 12120141871. Bosch is cheaper, not sure if that actually means anything.

Also, when you go to clean your MAF, I recommend getting a tamper proof torx set and actually remove the sensor from the housing and spray the sensor directly. Can't really spray the sensor very well with it in the housing. Doesn't need to be wiped down at all, just sprayed.

Exactly. Start with simple and cheap (plugs, MAF, possibly ICV cleaning), then work your way up.

[Bmwtvboy]

Good Vibrations: Almost have to give up for now. Replaced both motor mounts, got a $418. quote to change the auto tranny mount; did for $140 instead. Left the shop, very light,slight vibe. Great fixed it. NOPE, a half an hour later, six lights and it's vibrating like before. SO, I thought, sub frame bushings, but those are on the back? BTW, the engine is perfect. Had it checked out by two different mechs. NO leaks, Vanos is fine. It drives great, smooth acceleration, tight turns and gets great gas mileage. Only vibes loudly in cabin when in"D", almost disappears in "N". No problem in Park. One mech stated it really isn't doing any damage to engine, but very annoying. I guess that's why it's a BM Trouble U. Thanks for advice.

[racingbmwm3]

When the shops have looked at it, have they driven the wheels on the lift to a speed where the symptoms would normally show up? That would enable someone to look underneath to figure out where the vibration is coming from, either by feel or with a stethoscope if it isn't super obvious.
Sounding more like transmission or torque converter problems.

[Bmwtvboy]

There isn't any vibration, knocking or jolting when leaving a dead stop from idle either under idle or acceleration. No change in vibration when at stop, brake engaged and turning the steering wheel side to side. No change in vibration when engaging A/C, and the car has no change in movement forward from dead stop. Although not the same car, my old E30's vibrations that were similar to this came from the drive shaft/c.s.bearing. This area of the X is fine.
Starting back at engine source. But the engine runs sweet. BTW, when looking at the RPM dial where should the needle rest during idle, in "D" foot on brake?
On the line above the "0" or a needle thickness below the 1000 mark?
The RPM moves up slightly, about a needle thickness when shifted from"D" to N under braking.

[Kristophe]

Other than not addressing the vibration do new motor mounts add any improvement to ride/handling?

[Bmwtvboy]

A couple of years ago I rebuilt the front end with new Bilstien Shocks and always thought the ride was bit stiff, eventually over time the front end started bounce lightly, but uncontrollably. Then, after the recent engine and tranny mount replacements the ride is like glass. It is so smooth and handling is great. I put the tranny through it's paces tonight. Using the sport shift mode through all gears up and down slow and fast and it was flawlessly smooth.
My guess is ICV. When I changed out the intake boot and had to remove the ICV I noticed a large rubber grommet connector. I wondered if this should be replaced when putting things back together. Could removing and replacing this old grommet created a leak around the ICV? As for the ICV I didn't get to test it and I noticed that it didn't rattle at all, solid, not movement. I mention this because there are several utubes showing cleaned ICV's rattling when shaken. There is also a 12 volt ground test that can be done to see if the inner mech is rotating. Other than that I am stumped. I leave for Atlanta in couple of weeks to relocate for a new position. Hopefully I can find a great BMW shop in the area that can assist without braking the bank.

[Kristophe]

I concur on the ICV. Has to be the likely culprit.