Vibration Between 40-45 Mph

[rvtravel]

I have a vibration when driving at a steady speed between 40 to 45 MPH. It has gotten worse over time. After a Lexus technician drove it, he said the computer could not decide between running on electric or gas. He was told there was a software fix that was in test and should be available for upgrade soon to take care of this problem.

Has anyone else experienced this problem and has it been resloved?

[et1957]

i get that sometimes when in low speeds when i shift from electric to gas and trying to stay at a steady low speeds on the busy city side streets,,,i thought it was normal since it is where it usually shifts into gas anyways,,then turns off when i need to slow down,

[skyfish400h]

i get that sometimes when in low speeds when i shift from electric to gas and trying to stay at a steady low speeds on the busy city side streets,,,i thought it was normal since it is where it usually shifts into gas anyways,,then turns off when i need to slow down,

Are we talking about that heavy low frequency engine vibration where the engine is under load but not yet reving up?

When I'm accerating slowly from the light, ususally about the time I get to the other side of the intersection, there is phase (transistion if you will) where the engine seems to be taking on more of the load but is still basically at idle (say 1500-2000 rpm, i'm guessing). It does not last long under normal acceleration, but if I hold it there, I can create a steady state where this occurs. Feels like the engine is "lugging" (to use a manual transmission word).

I can see the same scenario playing out at hwy speeds, but the vibrationi would be less noticable what with the road vibraiton and wind etc...

[ravenwood]

I have a vibration when driving at a steady speed between 40 to 45 MPH. It has gotten worse over time. After a Lexus technician drove it, he said the computer could not decide between running on electric or gas. He was told there was a software fix that was in test and should be available for upgrade soon to take care of this problem.

Has anyone else experienced this problem and has it been resloved?

I have the same experience. I figured it was some sort of harmonic. A small variation on speed seems to make it dissappear for me.

[louis'ride]

I have a vibration when driving at a steady speed between 40 to 45 MPH. It has gotten worse over time. After a Lexus technician drove it, he said the computer could not decide between running on electric or gas. He was told there was a software fix that was in test and should be available for upgrade soon to take care of this problem.

Has anyone else experienced this problem and has it been resloved?

I have the same experience. I figured it was some sort of harmonic. A small variation on speed seems to make it dissappear for me.

[louis'ride]

Well, this might be the same thing I just wrote about. ( I thought it might have to do with battery charge.) The dealer shop forman told me they had some problems like this reported in the '06s, but not the '07s. Well mine is an '07 and I have it. They could only tell me to wait it out, the engine has to set. Is this true?

[skyfish400h]

Well, this might be the same thing I just wrote about. ( I thought it might have to do with battery charge.) The dealer shop forman told me they had some problems like this reported in the '06s, but not the '07s. Well mine is an '07 and I have it. They could only tell me to wait it out, the engine has to set. Is this true?

There's an element of truth to it. The engine mounts are dynamicaly dampened to isolate engine vibration from the chassis (kinda like noise canceling headphones). If the timing or the amplitude are not exactly right then you feel vibration. There is likely some learning that takes place in the car's brain whereby it learns to anticipate profiles where more damping is needed based on your driving habits, type of gas you use.. etc.