The mounts do not control the engine speed, but if you have a broken motor mount, you will feel the vibration a lot more. A 500 rpm idle in drive is SMOOTH, and you should not feel a vibration.

If you have a MISFIRE, it will vibrate at any speed, but a good running engine will be S-L-O-W, but be smooth.

Go and drive a new GS430. It revs high when cold, but once warm, it idles slow when in "drive". My 99 GS400 is just as smooth. Turning on the lights and AC significantly raises that idle to about 700 rpm or so.

When I changed my mounts, my engine suddenly felt smoother. The mounts were broken in a place that was not visible while still installed in the car. I knew they were broken when I shifted to drive, held the brakes, and lightly pressed the accelerator and released it quickly. The hood was open, and I could see the engine rise and fall suddenly with the accelerator pressure.

When I removed the mount, it was broken in the middle and the fluid inside had leaked out for the most part. That was where the vibration was.

 

I did that test with my engine mounts as well, holding brake, giving gas while in drive. I did not notice any significant movement. My SC430 has about the same amount of movement with half the miles. The SC vibrates as well. Newer car than the GS, less miles, and is already shaking. I don't know if this can be related to the mounts. Is there a way to test them or something. This problem is up there with the jerkiness on uneven roads problem.

Oh, and my boss has a new LS430. RPMs stay over 600 pretty much all the time.

How much are the mounts anyway?

 

With the 99 GS400, the idle can be raised slightly by adjusting the throttle cable. The newer (2001 and above) have drive by wire, and the idle speed cannot be adjusted. just keep your throttle body and ISC clean, and you have a good chance of keeping your idle up.

Diagnosing the motor mounts is hard. I checked it a couple of times and though I felt in my heart it was broken, I couldn't really see it. I have a lot of experience with motor mounts, and took a chance on a new one. Boy was I glad I did.

Once I took it off, I could see the damage, and how it was difficult to check while installed. The drivers' side is much easier to change than the passenger side.

The drivers' side mount cost about 70 bucks at Carson Toyota. By the way, the driver's side usually breaks more than the passenger side, as the torque is applied to that side when going forward, and to the passenger side when going in reverse. You can see each side lifting up going from forward to reverse.

GOOD LUCK!

 

Did you change both the mounts or just one? $70 is really nothing if this fixes the problem.

 

I changed only the driver's side so far, and that took out the vibration. The passenger's side is much harder to change, and I haven't done it yet, although I did buy the passenger side as well as the rear transmission mount. I have a real "rubbery" feeling whenever I shift to reverse and the car changes direction. I think the right side of the engine momentarily "bounces" up and down when I shift to reverse. I'll get that pesky passenger engine mount and transmission mount this weekend.

Because the gearing is different from forward gear to reverse gear, the vibration is more prevalent in "D". When in reverse, you'll notice that RPM's will be higher than when in drive. This is with the lights and AC off.

If you feel vibration in drive, but hardly any in reverse, then I would consider a drivers' side motor mount.

Good luck!

 

id i both when id id them and i did the tranny mount.. whern my mechanic took one motor motor mount out.. it broke into 2 pieces ... just so you kno... at 85k.. but i am a heavy footed river but i bought the car at 68k

 

You know what you may be right. I just tried it with putting the car in reverse, lights and AC off. The vibration was not there. In drive the vibration is there. I am going to get me the driver side engine mount first. And then the rest from there.

 

Low idle is bad in what way? I warm my car up and when the heat is up and the idle is relatively low (Under 1,000RPM) I figured it's a good thing.

 

It's a bad thing when the idle gets to low. There is a point where the engine struggles to stay running, when that happens it starts to shake.

Most stock V8's idle smoothly around 600. But with VVT-i they may be able to idle at a lower idle.

e-man believes his shake is due to a low idle issue. But engine mounts may also be the culprit.

 

i had the same problem-- wasn't happy-- searched for fixes and found an old discussion of this problem on the same site back in april of 02. so here is the thread with the fix that i did and it worked for me. it also made my car faster... and it was free... that is the best part in my opinion. -jah bless-

link:

https://www.clublexus.com/forums/arc...p/t-45441.html

for more fun stuff about this model gs check this page:

https://www.clublexus.com/forums/arc...php/f-186.html



~bbr

 

SOJAH??? i'm guessing u like soldiers of jah army? im a big fan

 

i replaced the engine mounts on my GS when i noticed the shaking and it got rid of the shaking.. the idle is still the same tho.. but i may go buy a tps sensor n replace it

 

has anyone tried the EFI fuse from the links above. Supposedly it fixed some guys problem a while back. Doesn't make sence, but worth a try.

 

i believe that pulling the EFI fuse is the same as pulling the negative terminal off the battery

 

hey slick i just told you it worked, so in response to your question "has anyone tried the EFI fuse thing?" Yes, i did it and it worked. i don't know why, but if you read the thread from the link i posted it does a pretty good job of explaining why. and like i said it made my car faster. and it was free. and like that other dude said disconnecting the neg. battery cable for a little while would do the same thing.

yeah soja is pretty cool, i have seen them a couple times. they are a little to politically aggresive at times, but i think they have good points... i used to live in d.c., actually gonna be moving back there real soon hopefully. i am getting out of the military and getting a better job.