I've noticed this since around a week ago. When I start from a standstill and accelerate at a decent rate, the car slightly shudders during the first 3 seconds or so. Anyone in the car can feel it. It's basically a rough vibration, as if the transmission is slipping or something.

I noticed another thread that mentioned that it could be overdrive, but I've used it for months now and this vibration has never happened. I also got my wheels aligned/balanced recently too.

I'm worried if this has something to do with the transmission or possible the fuel pump. Any other ideas?

 

Maybe the motor or tranny mounts? I've heard they can lead to some wicked vibrations.

 

sounds more like the infamous 1st gen hesistation issue, normally if its the trans or engine mounts it causes consistent vibration at a given rpm or rpm range, not just the first couple seconds of movement.

 

man....i always wondered what was that too coz my ls does the same thing. it sometimes does when i accelerate from 25-30 mph.

 

Hello,

I had the same thing. The transmission was maintained as supposed to be, but flushing the transmission, not just draining the 2 quarts solved my problem.
My transmission mount was not broken, even after 470000km.

Chris

 

I went to my Lexus mechanic and he flushed out the transmission fluid. It has so far fixed the vibration problem.

Would the first few hesitant seconds be something related to the fuel pump?
I ask this out of curiosity.

 

Not the fuel pump. It is most likely your spark plugs, wires, or caps/rotors.