Autonils1 Posted May 26, 2010 Report Share Posted May 26, 2010 Hi, on my newly purchased 320d '03 (07/02) with 5-speed automatic transmission and 60.000 miles on the meter, I am experiencing a strange humming/growling noise(/vibration), mostly occuring between 1400 and 1500 rpms (but sometimes at about 2500 rpms too). The noise is comparable to the "wake up" sound from driving on the motorway curb marking, although not as high. It lasts for about 1-2 seconds, sometimes longer, and happens when maintaining speed or during slight acceleration. So far I haven't been able to tell whether it is coming from the front or rear. No vibrations can be felt through the steering wheel. I am leaning towards the rear axle or gearbox / drive shaft, but far from sure. When the noise occurs, the odometer shows the revs varying by about 50-100, up and down. There is sometimes a slight "jerking"/surging sensation of the entire car. But the engine pulls smoothly when more throttle is applied. I seems as if the engine is unable to tell whether to accelerate or slow down (or maybe the gearbox not being able to shift when it should(?)). Could it be the torque converter failing? I tried an E90 with the same engine/gearbox and milage, and it didn't show any similar sympthoms. There is an oil leak from the diff. I checked the oil level which was a little low (could this have damaged the diff?), and filled to the appropriate level. No improvement at all. My BMW dealer says there is no error code stored as could be expected for e.g. a MAF sensor problem. I am dreading an expensinge trial-and-error approach from the dealer mechanics, with gearbox re- programming, changing sensors, etc. This problem is frustrating to say the least, and all help would be greatly appreciated... Link to comment Share on other sites More sharing options...
simonlpearce Posted May 26, 2010 Report Share Posted May 26, 2010 TBH i could be just about anything really, have you considered wheel bearings at all? Welcome to the forum though, hope you get it sorted. Link to comment Share on other sites More sharing options...
minicoopers Posted June 8, 2010 Report Share Posted June 8, 2010 TBH i could be just about anything really, have you considered wheel bearings at all? Welcome to the forum though, hope you get it sorted. Just stumbled across this thread as i'm currently experiencing the exact same problem/issue with my 330ci auto. Its doing exactly the same thing, at fairly low revs usually while driving. Your foot will be on the accelerator at at steady rate and then the revs will momentarily drop down then suddenly go back up to the normal position again. As this happens there is a bizzare groaning sound from somewhere on the car. Its very strange! i hope its not a torque converter issue as it starts getting expensive then. I know that my car needs a wheel speed or an abs sensor as my traction and brake lights are always on on the dash and i cant turn on or off the traction control. Could it be to do with a wheel speed sensor maybe? Any insight into this would be greatly appreciated. thanks in advance Link to comment Share on other sites More sharing options...
Mcfly Posted June 20, 2010 Report Share Posted June 20, 2010 Hi, Just wondered if you managed to source the problem causing your vibration?.. I got my car remapped yesterday (330d now at 220bhp) and Im getting a similar problem now. If im in 3rd. 4th or 5th gear and floor it from low revs, the car will 'shudder' intermittently a couple of times, lasting about half a second each time (as you say..just like running on the rumble strip on the motorway) and you can actually feel her backing off the throttle slightly (you can hear the turbo backing off too) until the revs build up to about 2000rpm and then she will pull normally. However if I set off fast and am quite aggressive in every gear, she will surge up as normal... odd! I already know that my drivetrain 'doughnut' needs replaced, and I was hoping it was just it suffering from the extra torque! My only other thought was that it seemed like the traction control kicking in for some reason. Any help on this would be good! Link to comment Share on other sites More sharing options...
gaz_36 Posted October 17, 2010 Report Share Posted October 17, 2010 Hi, Just wondered if you managed to source the problem causing your vibration?.. I got my car remapped yesterday (330d now at 220bhp) and Im getting a similar problem now. If im in 3rd. 4th or 5th gear and floor it from low revs, the car will 'shudder' intermittently a couple of times, lasting about half a second each time (as you say..just like running on the rumble strip on the motorway) and you can actually feel her backing off the throttle slightly (you can hear the turbo backing off too) until the revs build up to about 2000rpm and then she will pull normally. However if I set off fast and am quite aggressive in every gear, she will surge up as normal... odd! I already know that my drivetrain 'doughnut' needs replaced, and I was hoping it was just it suffering from the extra torque! My only other thought was that it seemed like the traction control kicking in for some reason. Any help on this would be good! hi im also having the same symptoms on my 320d auto 2003. its only doing it intermittently,i have had the car on obd with no faults codes the only thing that i have noticed is now and again the asc light will flash for a couple of seconds even though driving at a steady speed any help would be greatly appreiciated thanks Link to comment Share on other sites More sharing options...
Autonils1 Posted October 18, 2010 Author Report Share Posted October 18, 2010 My local BMW dealer concluded that the torque converter was damaged, and that it had to be replaced. Short of other options, I (reluctantly) had them go ahead and do it. They also flushed the gearbox, and changed filter and oil. Plus the gear box- and engine mountings, and the vibration damper on the engine itself. Just to be absolutely sure. When I got the car back, everything seemed to work perfectly. For a few miles....! Then suddenly everything was just as before. 3K++ completely waisted! And: the garage were out of ideas... I made a post on a local BMW forum, and (surprisingly) there was a prompt answer from a guy who had the exact same problem. The problem with his car had been fixed by upgrading the firmware on both the engine and the gearbox, and clearing the gearbox memory. I immediately had this done by the BMW dealer, who at first didn't believe that this would help. But guess what! The varying revs / surging sensation was gone. And have not appeared again (knock on wood!). One small problem remains, though; the rumbling noise is sometimes still there at low rpms, although less noticeable than before. My advice; try the least expensive remedies first! But these GM gearboxes have a really poor reputation. Re-mapping, heavy loading etc. should be avoided at all cost. A lot of people have learned this the hard way... Link to comment Share on other sites More sharing options...
suhail97 Posted October 18, 2010 Report Share Posted October 18, 2010 £3k?? Do they have big windows at the dealers cos they saw you coming from miles away!! Is there anyway you can get some of the money back as what they recommended didn't fix your problem. Link to comment Share on other sites More sharing options...
Autonils1 Posted October 18, 2010 Author Report Share Posted October 18, 2010 £3k?? Do they have big windows at the dealers cos they saw you coming from miles away!! Is there anyway you can get some of the money back as what they recommended didn't fix your problem. The mechanics (of course) totally disagreed that the torque converter change was unnecessary, claiming that the rumbling noise was a sure sign of torque converter failure. And they were really annoyed when I asked why they didn't suggest the simplest remedies first. (Of course they are unable to hear that the noise is still there...) I am lost for words... the degree of incompetence that has been shown here is beyond disappointing... Link to comment Share on other sites More sharing options...
Nose Posted April 5, 2011 Report Share Posted April 5, 2011 I've got exactly the same symptoms on my car, identical. I had the oil and filter changed in the gearbox, aswell as all the electrical connectors cleaned up. The rumble has decreased massively, but it still has that silly erratic rev when trying to maintain a constant speed. The garage said they updated the software but i dont believe them, either this or the firmware they have isnt as up to date as it should be. I will take it to the BMW dealer this saturday and see if they can update it for me. How much did this cost by the way? Really dont want anymore surprises after spending 400 quid on the box already :| Link to comment Share on other sites More sharing options...
touringpete Posted April 5, 2011 Report Share Posted April 5, 2011 I also have a similar problem with surging power on a light throttle, but i have a manual gearbox! i thought it could be something to do with the fly by wire throttle? ive tried doing the throttle re-set but this didn't do anything Link to comment Share on other sites More sharing options...
