It's my wifes car so I don't know when this started. I drove it the other day and it sounded as if the dash was going to shake loose. The car vibrates badly at idle. It smooths out somewhat at higher rpms, but I can tell it's still there. I've replaced the motor mounts. The driver's side was definately bad. The other two were good(I know this after having replaced them). What else could it be? It used to get better as it warmed up but now it stays the same(per wife). I checked the plugs-all looked same(good color). No codes. Gets the same mpg as usual. I can feel it when I put my hand on the valve cover. It's not as smooth as it used to be. Could something be hitting the body/firewall/k-member somewhere? I can't figure it out[dunno]. 150000 miles. Timing belt replaced 20000 miles ago.
09-12-2012 04:42 PM
How long ago were the mounts changed? My car only had 72k on it but the mounts were crap! Did you get OEM mounts as well?
09-12-2012 06:21 PM
Could be mount, but I have 250,000km's on the originals and have no vibe issues.
When my o2 sensors were going out had a vibration decelerating at around 2800rpm's, but nothing that would rattle my dash!
09-13-2012 02:19 PM
I replaced the motor mounts on Tuesday(2 days ago). Before I replaced them, I put the car up on stands and then placed a floor jack under the tranny where the rear mount attaches. I started it and it was smooth as silk. So I replaced it. Started it and the vibration was still there. Have replaced all 3 mounts and still vibrating. Not as bad as before but close, more than I'm comfortable with. My wife drove it to work(70 mile round trip) and said it felt about the same to her. It seems worse at idle. She has to drive it, this weekend I'll get under it again to see if I've missed anything. Is there anything in the engine that can get out of balance? I've had it torn down to the a long block(block, pistons, crank, and pan) and don't remember anything that could get that out of balance. I'll follow up after I look again this weekend. It still has the original flywheel and clutch, but no slipping. Like I said, it's the wifes car and she baby's it. It's never seen 5000rpm but about 4 times.
09-13-2012 04:25 PM
What did you replace them with, OEM or aftermarket?
Slim possibility that a pully is going out, maybe, but I can't think of any rotating items that would cause this other than a clutch or flywheel issue, also maybe!
What is the engine idling at when you feel this vibration?
09-13-2012 09:00 PM
timely post. My '02 SVT with125000 miles is showing same symptons. Worse when cold,better after warmed up. Almost sounds like exhaust rattle but can find nothing wrong. Will follw this post closely. Good Luck!
09-14-2012 09:16 AM
Replaced with OEM mounts. I can't remember what the idle rpms are, just know that it's the same as it always has been. I'm thinking around 700rpm? I was thinking maybe the flywheel &/or clutch too??-maybe. That would be the only rotating mass that I thing could cause a vibration of this magnitude? I want to eliminate all the other possibilities first. I hate pulling that tranny out. I shoulda replaced all that when I had it out summer before last, but money was tight. I'll give it another look this weekend and update then.
10-10-2012 10:19 AM
Sorry for being late on replying. I hurt my back and couldn't check the car out again until recently. I put it on stands and checked everything. Nothing that I can see is hitting anything. I thought maybe that I had left something loose, but no. I checked the crank pulley/balncer to see if the rubber had separated. It looked good. I cannot find what's causing the vibration. Desperate, maybe stupid question here: can the (dual mass) flywheel get out of balance? I hate taking my cars to a garage, but I've got to get this resolved. Does anyone have any ideas?
I'm thinking something is hitting somewhere. Because at times while driving the vibration goes away for an instant. Like something is shifted/moved and there's really no pattern to it. I've applied the e-brake and put a load on the drivetrain in both forward and reverse to see if the vibration changes with no luck. Sorry for rambling, just trying to give all the info. I can. [?|]
12-17-2012 09:22 AM
An update. I didn't tighten the nut on the underside of the passenger side motor mount. To sum up the cause of the vibration: both the driver side and passenger side motor mounts were torn. I replaced all 3 and the vibration is gone.