i need help i my car virates

[bmwhighrolla]

hi i just bought a 1998 323is 4 days ago. it has this vibration when its gets above 2500 rpms and i dont know what it is. now it was looked at by a bmw dealer from the previous owner and he said he was told it was the exhaust. i am ready to replace the exhaust system but cant afford it. i am only 17 and it hard enough paying for car and rent and bills

supposibly how it happened...
it was the guys first car and he didnt know what the signes of a clutch going and when it when he high reved it to the side of the road. ever since its been doing this... that was a year ago. supposibly it doesnt effect the car in any way but the vibration but its anoying

i want my bimmer to ride like a bimmer can anyone help??? [bmwkick]

 

[bmwhighrolla]

i was doing research and i was reading about this flap in the tail end that make the car "run quieter" in loe rpms its run by a vacum hose i now have that diconnected and it still vibrates the same. but it sounds nicer.

 

[Tom]

lol, sounds nicer huh? I guess the best thing to do is leave it alone and replace the exhaust when you have the money to see if that resolves the issue.

 

[bmwhighrolla]

not good enough you dont know how annoying it is and not to mention embarassment oooo you got a bimmer wtf it rides like sht

 

[Faze]

the exhaust isn't going to affect the ride. It will affect the sound... and I guess if it was vibrating bad enough it would be felt inside, but it wouldn't translate to a ride condition. What is really going on with your car, dude?

-J

 

[frolf]

get under your car and jerk crap around til you find whats loose and what isn't. i had a nasty vibration at 30mph, no matter the gear, and i figured out that when i had my clutch done they forget one of the bolts on the guibo. i had another vibration at idle one time, once under the car it was easy to see the heatshield above the exhaust was missing a bolt. i'm a crappy mechanic but its not to hard to rattle stuff and see if its actually on or not.

 

[bmwhighrolla]

i have no idea what it is its not a rattle tho you dont hear any thing you just feel
when i am driving a vibration starts at 2500 rpms i fell it most in the shifter and the floor the driver is really the only one who fells it others feel it but not as bad as the driver

bmw dealers tol the previous owner it was some flap in the exhaust and the whole system had to be replaced.which i think is bull because there is multiple parts to an exhaust that can be exchanged i doubt every part is bad

 

[bmwhighrolla]

aLSO i would got under there but right now its -10 with the wind chill

 

[Tom]

The only other thing I can think of that causing the vibration is a broken or loose motor mount. Engine vibrating at a certain RPM is a good symptom.

Their not too expensive and you can buy them from AutohausAZ.com
1) Select Make/Year
2) Engine Parts, Seals & Gaskets / Engine/Motor Mount

 

[bmwhighrolla]

i had bad motor mounts in my old car aND the car would shake constabtly even at idle i dont think its motor mounts

 

[Kirby]

All you say is at 2500 RPM. Does it occur ONLY when driving, or does it also occur with the car in neutral and sitting still, and reving the engine to 2500 RPM?

 

[bmwhighrolla]

yes when it is in neutral it does it still when i rev it so it aint tires or suspension or anything - the car doesnt shake when at idle and the engine dosent move when i rev it so its not engine mounts

i just want my car to run smooth :'(
i am paying 160 for a 1999 m3 cat back exhaust just because i love the sound of the m3and because i am going to start replacing the whole exhaust little by little i am going to be p'ed off if it doesnt fix the problem. but i think either headers or something aroun the cat i am going to go uner there tomaro its supposed to be a little warmer and ill let you guys know whats up if anything is loose or what

 

[bmwhighrolla]

exhaust is tight guibo is like new i think bad tranny mounts from a shitty install of clutch

 

[epj3]

exhaust is tight guibo is like new i think bad tranny mounts from a shitty install of clutch

Now that you say the clutch was replaced - I am willing to bet they DIDN'T mark the driveshaft at the expansion coupling.... and if they didn't mark it - they probably didn't have the tools to rebalance it after putting the driveshaft back in.

Your driveshaft could be off balance becuase of being put back together at the wrong position. If its even one off one flange (like mine accidently was after I replaced the center bearing), it will vibrate.

http://www.bmwchannel.com/eric/clutch/100_5806.jpg the flange is up there

http://www.bmwchannel.com/eric/clutch/100_5811.jpg thats the REAR half of the driveshaft (you can see my chalk lines - the other half of the driveshaft has the marks at the same position)

http://www.bmwchannel.com/eric/clutch/100_5809.jpg you can see the chalk mark on the OTHER half of the driveshaft... if the driveshaft isn't put back together lined up, it will vibrate!

 

[bmwhighrolla]

now even if i can rev it sitting still in neutral it could be the drive shaft?
would the vibration only start at 2500 rpms wouldnt it do it all the time?

 

[epj3]

now even if i can rev it sitting still in neutral it could be the drive shaft?
would the vibration only start at 2500 rpms wouldnt it do it all the time?

Sorry, I didn't see that

The driveshaft only spins when you're moving. Sounds like it might just be running rough??

 

[bmwhighrolla]

well i am in the process of gettin my tranny mounts 24 bucks not bad i refuse to go to the bme dealer!!! 70 an houa is rediculous!! hopefully this will fix it but now i got a new problem my ignition is messed up somone help me on wat else i can do besides wat i have done and change the tumbler??