I know there is a lot of vibration talk around here, but my problem seems to be of a different nature and all night of searching posts hasnt lead me to a conclusion. Im no expert, but I don't think this is a CV joint or axle b/c it doesn't seem to be correlated at all to car speed, just engine revs. I mostly do city driving, but last night i drove some 200 miles on straight freeways and it was much more noticable than in stop and go driving. I did some playing with it on my 3 hour road trip, attempting to figure out the source (tire, axle, engine) and here are my attempts at precise observations:

Driving at a constant 70 mph with 3k rpms: barely noticable

Accelerating from 70 to 80 while leaving the car in 6th gear: vibration strengthens in direct proportion to how hard I press the gas/how quickly I attempt to accelerate to 80.

Push in clutch and let engine revs drop to idle while coasting at 70, 80, or whatever: vibration is gone.

drive at 70 and in 6th and vibration is a slow frequency, drop down to 5th gear and maintain speed of 70, vibration is a faster frequency.

Vibration is felt at lower speeds, for instance in 2nd gear when accelerating hard from 2.5 k and upwards, but it is not nearly as pronounced b/c the engine isnt under as heavy a load and can rev more feely. It is at its worst when the engine is under the heaviest loads, ie accelerating in 6th gear w/o downshifing.

I really need some advice here. My 94 mcs has 56k miles and I really dont want to go to the dealer and have them start changin random parts and charging me until they finally find teh problem. Im hpoing tihs isnt some indicator that my engine is on its way to self destructing, could it possibly just be time for new engine mounts? Regardless,any and all feedback is welcome.

 

Start with the motor mounts and tranny mount. You may want to use the OEM rubber ones or the aftermarket poly. I bet it's the big upper mount on the pass side of the motor. You could replace just that one at home and see if it helps and then move on to others if needed.

 

I just looked at 2 of the mounts, one appears to be fine, but the large fat one sorta near the super charger pulley does not look right to my eyes. Then again I dont know what it is supposed to look like. I dont know how to insert pics here, but i uploaded some to my gallery that i just snapped on my phone of the suspicious rubber mount. Thanks yall.

Dean

 

Heres the pic of DeanoTX front mount.


I've not seen enough of the older one to know if this one is bad or not. I'm sure others can look at it and let you know.

 

i dont see any cracking...

 

Did you ever figure out what it was? I have the exact same symptoms. Just got tires rotated and balanced and it's still there.

 

My thoughts are belt tensioner/belt. It should be easier to hear when just sticking your head near it as a buddy revs a bit.

 

I have the same issue.. 2500 rpm and it vibrates the car ! Nothing exhaust related, I spent a good hour with my exhaust guy and found nothing.

 

Per the photo above, that appears to be a collapsed engine mount. The '02 and '03 MCS use a large rubber one with a small amount of damper fluid inside it. The '04-'06 MCS has a completely hydraulic one. In many cases, you will read stories about owners having fluid leak all over the place. The one in my old '02 MCS actually leaked out what little fluid was in it, but it still functioned somewhat well.

When you look at the '04-'06 MCS mount, there should be a 1/4"-1/2" space between the mount top and bottom (i.e. the two parts that comprise the hydraulic mount). The best way to see if it is collapsed is to get down one one knee about 4-6' back from the front of your MINI and look at the level of the engine. If it appears to be leaning to the left, the mount needs to be replaced.

The one in my current '06 MCS was collapsed when I bought it, and it had 40K miles at that time. I upgraded to the TSW solid polyurethene mount, which is now owned by Way Motor Works (http://www.waymotorworks.com/). They are about $200. The good thing is it should never fail. The bad thing is the engine harmonics are much higher throughout the MINI. It's especially bad if the temperature outside is below freezing. As long as you can deal with that, I recommend the upgrade.