flipmode64

Hey Guys,

Have a 91' LS400 and it has vibration through the gas pedal when the revs are between 1200-1600. so around 40-50 kph...

Looking through some of the old receipts I got from the previous owner there was a driveshaft replacement, and it was taken back after that and it was "adjusted"... but still the vibration is there.

What things should I be checking here? Tried to do a search but everything I came across was related to braking vibration, not gas pedal vibration.

Thanks!

flipmode64

Anyone have any suggestions what to check, and would it be the drive shaft? even if its been replaced and adjusted already?

mikes7ke

iTrader: (1)

The gas pedal is linked to the engine by the throttle cable. I'd check the cable bracket, engine mounts, trans mount first. Maybe the fan clutch or bracket.

3UZFTE

Does this vibration happen in Park or Drive, or both? If you are in Park or Neutral, the driveshaft will not be rotating, which would eliminate any problems with the driveshaft. If you notice it at all times, than it could possibly be related to the driveshaft, but I would be skeptical....

I would be looking at the engine mounts if it is not present in Park or Neutral. As stated above, the gas pedal is connected to the intake manifold, if the whole engine is shaking, it could cause the pedal to shake. But usually motor mounts would cause the rest of the vehicle to possibly shake a little bit, depending on how bad the mounts are worn.

johnnyg66

I have a similar thing on my 92 in overdrive hits 75ish slight sometimes intermittent vibrations around the same rpm 1700. Higher it fades off some. Feel it in steering wheel and thru floor. Have done replaced all the front end stuff over the past year. Has gotten lots better. Ordered my engine mounts today so thats the next step. Already did trans mount.

3UZFTE

When's the last time you've had your wheels balanced?

johnnyg66

Bout a month ago got new tires.