94 540i vibration problem. Part Deux.

[rcbrown23]

Ok, lets try this again. 1994 540i with auto transmission. First off, let me tell you what happened:

Sitting at a red light waiting to turn left. Light went green and I punched it and took a left turn. Well, right as I punched it, something broke. Now there's an awful vibration at all speeds as I accelerate. No vibration while coasting, and no vibration while braking, but if I get it up to about 35-40mph, the vibration gets really severe, and I can feel it in the shifter also (hell, I can SEE it in the shifter).

I posted here a couple months ago about it, and people seemed to think it was the guibo (flex disc), so I got under there and had a look. Well, I didn't see a guibo at all, and I'm assuming this year with the auto trans doesn't have one?

I did, however, see that one of my center exhaust brackets had broken off and the exhaust was hanging pretty low. I assumed that was the problem, and yesterday I replaced both brackets and rubber hangers. Got in the car happy with my work, and drove it only to find the problem is still the same.

Now I'm back to square one and don't know what it is.

Any help????

Just from searching the boards for a couple hours, I'm think maybe the center bearing? or the CV joint, or U-joint? or...?

Can anyone explain to me the easiest way to narrow this down? I've got a friend with a lift, so in the next couple days, I'll probably lift the car and have a detailed look under there. The bad news is that I'm NOT very mechanically savvy (at all), and I just don't know what I'm looking for. When I know what's wrong with a car, I'm usually pretty good at changing/replacing things, but not finding the problem itself.

Any and all help much appreciated.

-brown

[yaofeng]

The guibo is on every BMW. It is just behind the transmission.

[bsell]

The guibo is on every BMW. It is just behind the transmission.

Sorry, but my 09/94 build 525 auto has a solid plate where the guibo should be. At least that's the way it looked last weekend when I changed the oil.

I figure the OP ripped up the left motor mount, as seen by the broken exhaust stuff and the vibration only on acceleration. Suggest opening the hood, setting the parking brake, place tranny in drive, and slowly give her some gas and watch the engine climb out of the engine bay.

Brian

[yaofeng]

Do you call #2 a solid plate?

http://www.realoem.com/bmw/showparts...85&hg=26&fg=10

If #2 is not what you saw, either you or the PO put in something different.

[rcbrown23]

Thanks yaofeng... I'm going to go have a look here in an hour or so.

bsell, that's exactly what I *thought* I saw also. Like I said, I'll go check and post results.

[Tiger]

Don't forget engine mounts.

[JD525IA]

Ok, lets try this again. 1994 540i with auto transmission. First off, let me tell you what happened:

Sitting at a red light waiting to turn left. Light went green and I punched it and took a left turn. Well, right as I punched it, something broke. Now there's an awful vibration at all speeds as I accelerate. No vibration while coasting, and no vibration while braking, but if I get it up to about 35-40mph, the vibration gets really severe, and I can feel it in the shifter also (hell, I can SEE it in the shifter).

I posted here a couple months ago about it, and people seemed to think it was the guibo (flex disc), so I got under there and had a look. Well, I didn't see a guibo at all, and I'm assuming this year with the auto trans doesn't have one?

I did, however, see that one of my center exhaust brackets had broken off and the exhaust was hanging pretty low. I assumed that was the problem, and yesterday I replaced both brackets and rubber hangers. Got in the car happy with my work, and drove it only to find the problem is still the same.

Now I'm back to square one and don't know what it is.

Any help????

Just from searching the boards for a couple hours, I'm think maybe the center bearing? or the CV joint, or U-joint? or...?

Can anyone explain to me the easiest way to narrow this down? I've got a friend with a lift, so in the next couple days, I'll probably lift the car and have a detailed look under there. The bad news is that I'm NOT very mechanically savvy (at all), and I just don't know what I'm looking for. When I know what's wrong with a car, I'm usually pretty good at changing/replacing things, but not finding the problem itself.

Any and all help much appreciated.

-brown

It's fairly cheap and not too difficult. I had mine go out when pulling away from a stop sign when I punched it. When mine did go, the symptoms were exactly like yours.

Check it out.

JD

[BigKriss]

transmission mounts maybe, time to remvoe the exhaust and look at the driveshaft and it's related components.

yaofeng, a lot of 525 and 535's don't have a guibo. I know mine doesn't.

[rcbrown23]

Well, mine DOES have a guibo, and that's the problem. I don't know where I was looking last time, but I pulled it up on a ramp, got under there, and sure enough, the flex disc is mangled all to hell.

I'm actually glad that's the problem, and not something more difficult.

Ordering one now, and changing it out next week.

thanks for the replies

[yaofeng]

transmission mounts maybe, time to remvoe the exhaust and look at the driveshaft and it's related components.

yaofeng, a lot of 525 and 535's don't have a guibo. I know mine doesn't.

I'd like to know what you have. I am sure many others would be interested too. Do you have a picture or could point out from the parts catalog?