nofxdenk 0 Report post Posted February 2, 2012 (edited) Hi guys, Please help me to diagnose the problem with my E46 330CI M54 Auto, 160k The car started vibrating very strong when in idle. The vibrations have low frequency and go throughout the car you can feel it with your bum and feet and hands and it is everywhere on the steering wheel, on the seats etc - the whole thing shakes like there is no tomorrow..... Very annoying and very loud with windows up. The vibrations seem to be stronger stationary when in D or R and the right foot is on the break (engine loaded with transmission). RPMs stay constant - no jumping around at all. When pulling into a stop the RPMs dip to 500 - 550 and then stay at 550 or 600 or 650 kinda hard to tell, but that range there. As soon as some accelerator applied and RPMs go up to about 800 - smooth as silk, no vibrations, pulling nicely, power seems to still be there, gear changes are smooth as well... So far have tried: Scanning the car - a few error codes, mostly interior lights, seat occupancy (caused by the GROM audio box). In DME there were 2: 1 - oil level sensor (it is broken) 2 - MAF readings were a bit low, they were at 0.65 volts and the range is 0.6-1.5. And in transmission there was 1 - something about a solenoid stuck open... Clearing the errors and driving for 5 minutes - neither MAF error nor Transmission came back. also... Replaced air filter - no difference to vibrations Unplugging MAF sensor to force the ECU to load the default values for air/fuel mixture - no difference to vibrations Cleaning ICV (it was pretty dirty) - made no difference, in fact the strong vibrations began about a week after ICV cleaning. So i am not sure where to go from here..... Google says it might be engine / gearbox mounts, but how do you check them to be sure it's them? From what i can see the engine mounts look ok... Any help will be appreciated. Edited July 1, 2012 by e46beast Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted February 2, 2012 Who scanned it ?? Quote Share this post Link to post Share on other sites
swordfish 30 Report post Posted February 2, 2012 I am not sure what kind of vibration you get, but I would check the fan clutch! I had similar vibration on my M3. And I've noticed that bearing on the fan clutch was very loose, so the fan would create vibration through the whole car, as it wasn’t rotating in a perfect circle. It would have been very ugly if it would break while driving. Apparently makes a big mess in under the hood. So I would check it just in case. Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted February 2, 2012 The fan is a possibility. Can also cause the front knock sensor to kick in. I can check it for you next week if you like Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted February 2, 2012 Does the vibration cease if you hold the fan ?... you might need 2 people to do this. Stop engine, hold fan...someone else start and dont rev engine Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted February 2, 2012 I cant find brave enough people to test that Glenn, but the vibrations are almost non-existent when the engine hasnt reached its operating temperature. It is definitely at its worst when the engine is hot. You hold the fan and get a girl to start the car Quote Share this post Link to post Share on other sites
swordfish 30 Report post Posted February 2, 2012 You should be able to see whether it is rotating in the wrong motion more oval than circular (e.g. some blade edges are shaved off or if you shine the light between the fan and your clutch see if there is any marks or signs of wear on the water pump shaft). My bearing was pretty bad so I had both back and forward movements as well as side to side. It is most likely to vibrate more when your car is warm because you fan clutch is engaging the fan more when the car gets warmer, mine was exactly the same! I did the procedure Greg has described, just held the fan when the other person started the car. I wouldn't say it was the safest one though lol I would try move it side to side and look for that wear on the blades first. Cheers Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted February 2, 2012 Greg ??? Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted February 2, 2012 Bring it in tomorrow and I'll have a quick look. Maybe we can resolve it a little quicker than talking about it on here. Please ring me first though.. any time after 7.00 am Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted February 2, 2012 Be there at 7.30 Quote Share this post Link to post Share on other sites
swordfish 30 Report post Posted February 2, 2012 Greg ??? Lol Sorry Glenn... Was at work and my bosses name is Greg. Probably was thinking how he would kick my ass if he saw me on the forum during work. Hence, the mix up Hahahahaha Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted February 3, 2012 So i went to see Gavin from Euro-Italian about some engine mounts and when i got them was surprised to see that the mounts currently installed on the car are from an E30 I wonder who did that ??? BTW: Nice to meet you this morning Denk Quote Share this post Link to post Share on other sites
Carl 3 Report post Posted July 15, 2012 Last time I had vibrations it was the gearbox mounts, was low rpm but under braking you could hear something weird, turned out the whole drivetrain was moving a little and just before I replaced them the front fan just nicked the radiator so good I replaced them before it worsened. Quote Share this post Link to post Share on other sites
