Whenever i'm cruisin along at around 2K rpm's or lower and give it some gas, my shifter starts bucking back and forth pretty badly. I just replaced the opti(which solved my high rpm problems) , newer O2 sensors, about a year old tune up, and i just put new wires in as well. I was thinking maybe tranny mounts or maybe u-joints? Any help is appreciated

 

Tranny mount is about to go, get a poly one nexgt time and it will stop. I had the same problem!

 

thanks alot! im gonna go grab a new one now

 

Probably not the tranny mount the way you describe it. You say you just put in new wires, check them all. You probably have a burnt or loose wire. I had the exact same problem when I burnt a wire. When you're running on 7 cylinders it will shake bad under load at low RPM's.

 

it sounds like a miss. I would look into a burnt wire or a two that are switched around.

 

Sounds ignition related to me, too. They are noticed more in higher gears and lower rpm.

 

I am a firm beleiver indoing the cheapest thing first. You will enjoy a prolly mount anyways and it only take like 10 min!

 

Does checking for burned wires and the correct wiring cost something now-a-days?

 

Damaged tranny mounts are a lot rarer on M6's. I've never damaged one in my car and i've never known anyone with an M6 too do so. Everyone i know that has an auto has done it several times though. The point of my post is, he has a M6

 

yea i just checked the mount and it seems ok. The thing is that this was happening before i replaced the wires and opti so i think it may be somewhere else. I can recheck the wires and all that again but im pretty sure i put them on in the right way according to this pic
http://shbox.com/1/opti.jpg

oh and it happens in all gears at low rpms, not just the higher ones. once it gets past 2-2.5RPMs the engine runs great

 

im no expert mechanic or anything, but i dont think you need to be an expert to know that when you look at plug number 4 and the wire isnt even connected to it that there could be a problem
needless to say ive got a v8 again instead of the v6 i had before i changed my opti

 

Not trying to hi-jack thread here... but how about when you slam 2nd and the shifter shakes? Or sometimes when you pin 1st at like 3000

 

Did you check the plugs? Listen to the injectors to make sure they're all working, you should hear a clicking from each one. Check those connections as well. It really sounds like a dead cylinder, especially since it goes away at higher RPM's.