What, if any, would be the noticable driving issues if I had a bad motor mount?

 

None, just added vibration from the engine.

 

Thx, that's what I thought but wasn't sure.

I've been having a little engine thud feeling when taking off from a stop. It doesn't feel like transmission type jarring.

 

I have a thud too and just got back in from checking the transmission mounts which seem to be fine. My idle vibration is pretty low, especially since adding the GIAC software that put the idle speed up a tad. Next on the list to check is the snub mount, the rear diff mounts and driveshaft center bearing support.

 

A thud is usually the snub mount.

 

If you HAVE a busted motor mount, you depending on which side, by rotation, you would "feel" the engine lift off the mount and plop back down.

Most engines turn CW, so when you rev, it will pick up the passenger side, bump back down when gears change, tough enough engine, maybe in 2nd gear, too.
It really is not a good situation to be in.

Were you to replace your own, I haven't checked, but have bought one for a '90 5 cyl, used, for 30 bucks. Installing, if you can't do it, probably a couple hundred more, at least.

Cheers,

George

Oh, Auditech.
The front snub mount. I don't know for sure, but if you broke a motor mount, would the snub mount keep the engine where it was supposed to be if motor mounts went south.

Silly me, I thought the snub mount was to keep the entire drivetrain from winding itself up through the hood, seeing as Audi refuses to make crosswise engines. They are fore and aft, the entire drivetrain, and without the snubber, they would rock so much that we would have to use such anchors as GMC does with "dogbones", anchors to keep the engine from rolling it self out of the motor mounts.For every action there is a reaction.

Torque something, and anything not securely anchored is going to respond.


George

 

I've found out that you can't just visually check motor/tranny mounts. They may look fine and if you try to push/pull around them using your hands, you'll not be able to tell anything is wrong.

The best way to tell is to put a floor jack under there, find a good point near each mount and jack it up to see if the mount is actually in one piece. WARNING: Do not jack it up to fast or high, as you may damage a good motor mount. Do it nice and slow and you should be able to tell without a problem.

 

Exactly what I did, then I loosened the 2 bolts to see if I could twist the mounts by hand while it was jacked up. I still have to check the motor mounts, but I fear that is where my problem is. Looks like a PITA to change them on the 2.7T.

 

Thanks for the responses...

gmatov, your description of what is happen is a good description of what it feels like is happening.

Does anyone have a diagram or picture of where all the mounts are that I can visually inspect.

Thanks again,

 

After doing a little bit more research I went out and looked at the snub mount and it appears to be cracked up pretty bad. I guess It'd be a good start to have that replaced.