Solution - Buy new (re-manufactured) torque converter and install.
2016.4.22 - I changed the transmission fluid and added two Lubegard additives. It's only been one day and so far so good. I will report back in a couple weeks time.
2016.4.27 - Everything is still good, the shudder has not returned.
2016.5.20 - Shudder returned
2016.6.18 - broken leg.. repairs will have to wait
2016.11 - ordered remanufactured TC and installed. Shudder is less, but still present
2016.12 - TC has broken in and I do not have any shudder anymore.. finally, yay!
Original Post:
Hello, looking for some help to diagnose my 328xi Shudder/Shaking Issue
Here is the info on the car:
2007 BMW 328xi Wagon
~101,000 miles
I already took the car to an indy shop Sterling, VA and they could not correctly diagnose the problem. I've taken the car to BMW and they told me it was software and coils, which we fixed, and they did not solve the problem. The indy shop told me I needed new driveshaft flex discs, and that while doing that job they could take a look at the transfer case (it was leaking oil) as it could be a contributing factor. They also said the engine does not seem to be the problem and they ruled out coil packs causing the issue. They noted that the engine mounts seem to be ok, but that with a prybar they were able to move the engine, so there is signs of wear. BMW said it was an engine problem and not drivetrain.
I bought this car a few month ago and it needed work right away. I replaced the battery, water pump, thermostat, valve cover gasket, valve cover, valve cover screws, spark plugs, and eccentric shaft sensor.
Now on to the problem. After the car has reached full operating temperature, the issue starts to present itself. Basically, the car shudders/shakes when applying the throttle just a little (~1-8%). It happens at all speeds, and only in the 1200-2500 RPM range. It happens in non-sport mode and in sport mode, but more so in non-sport mode, due to lower RPMs. It does not happen when the car accelerates at a good pace, and does not happen at WOT. I am also noticing that the shaking/vibrations happens during shifts under light load.
The indy shop said they could replicate the problem when they were cruising at about 40 mph and then applied 2-5% throttle. For me it happens constantly on my 25 mile commute to and from work. It takes about 10-15 miles of driving before the problem really starts to show up and the stop and go traffic intensifies the shaking. It feels as if I am going over rumble strips, but there is no noise. Going up a hill exacerbates the issue and the stuttering/shaking happens more frequently.
After taking the car to the indy shop:
1 - I replaced the front and rear guibos and the center bearing on the rear driveshaft.
1.1 - This did not resolve the issue.
2 - I removed the front driveshaft and drove around.
2.1 - The issue was still present.
2.2 - I re-installed the front driveshaft.
2.3 - Issue must reside within the rear drive-line or engine.
3 - I replaced the rear output shaft seal (item #3 in the image) as well as the o-ring (item #5), drained and filled the transfer case fluid, replaced the fill and drain plugs, had the transmission learning reset, and had the transfer case programmed for its new oil.
3.1 - This did not solve the problem.
3.2 - The transfer case was leaking from the o ring, and not the seal.
3.2.1 - I suspect do to the shaking/vibrations.
3.2.2 - Replaced the seal anyways.
3.3 - I thought maybe the fluid was low due to the leak and the clutches in the transfer case were not working properly.
Not knowing what to do and not wanting to waste money, I took the car to BMW for diagnostics. They told me the entire car needed to have its software updated because it was still running its original 2006 software and that the ignition coils were causing the shaking. The tech's notes said, "Vehicle let idle at operating temperature, with slight tap on gas pedal, vibration was felt on engine. Vehicle test drove and vibration felt at all speed around 1800 RPM with light load on engine. Smooth running value checked to verify erratic spike on reading for cylinder 1 and 3 after short test. Removal on ignition coil to verify vehicle has 2006 (possible original) ignition coils. Replacement of all ignition coils, plugs* and resealing valve cover* recommended." *I just replaced the plugs and valve cover less than 1,000 miles ago. All of this lead him to believe that it is an engine problem and not a drivetrain problem.
4 - I had BMW update all of the software on my car (took 10+ hours to do this).
4.1 - Did not resolve the issue
5 - I ordered and replaced all ignition coils.
5.1 - did not resolve the issue.
6 - Replaced the transfer case actuator motor
6.1 - this did not solve the problem
6.2 - the original motor gears show no signs of wear
I had 3 suspicions as to what the problem is before taking it to BMW:
A - The rear driveshaft is messed up (unbalanced, bad u-joint, etc) and needs to be replaced/refurbished.
i - I have read about “harmonic vibrations” where things hit a certain RPM which resonates the rotating piece and causes the vibration.
ii - Could be a bad u-joint causing the shaking.
B - Something with the transmission because the car sometimes shakes when shifting, but that could also be due to the driveshaft shaking at different RPMs.
i - This is just my own thoughts, not really sure about it, maybe a slipping torque converter?
ALL I WANT TO DO IS STOP WASTING MONEY ON SOLUTIONS THAT DON'T WORK.
Hopefully I've done a thorough job describing my issues, but please feel free to ask me for any additional details you think would be helpful.
Does anyone have any thoughts or suggestions?
