Can You Feel The Engine Is Running At Idle?

[eddielasvegas]

All,

I had my motor mounts replaced a couple weeks ago and the vibration and shaking at idle (and in park) while at a stop light disappeared. Feels exactly like an LS should: like nothing is happening. Simply cannot feel the engine running now.

My LS only had 86,000 miles, but at 10 years old, figured they needed replacing.

Eddie

This is a good thread. I had my tranny mount replaced a few months ago and it made a noticeable improvement, but I'm still experiencing what others here are. I'm having the motor mounts replaced next week and will post an update here.

Bali26: Are those the steering rack grommets? Also, do you have part numbers for them?

Thank you.

Eddie

[qha_vn]

had my motor mounts replaced a couple weeks ago and the vibration and shaking at idle (and in park) while at a stop light disappeared. Feels exactly like an LS should: like nothing is happening. Simply cannot feel the engine running now.

My LS only had 86,000 miles, but at 10 years old, figured they needed replacing.

Eddie

thanks Eddie for your comments, i am saving money :)

btw, what did you replace? engine mounts, tranny mounts, steering rack grommets or all of them?

[SKperformance]

How much did the parts you ordered cost from Carson.

Also The mounts isolate the vibrations not cause them. The reason you have vibes is because something is not firing properly.

I had a similar vibration noticeable most under highway cruising. The vibe on mine was getting more and less in a smooth wave back and forth. It is similar to the computer rich /lean mixture made to test the cat and o2 sensors. After changing the 2 after cat sensors the vibe has gone away even at idle . It is firing much stronger and getting better gas mileage.

So even though i could use new engine mounts it is the effect not the cause.

[eddielasvegas]

Tranny mount replaced in Jan. with a noticeable improvement. MM's replaced a couple weeks ago with a bigger improvement.

No grommets or bushings replaced at this time. I can do those when I get a chance so no rush.

MM's were about $90 each (+ shipping) from Carson. Carson Toyota (Gordon and Loius) was great to deal with.

Eddie

had my motor mounts replaced a couple weeks ago and the vibration and shaking at idle (and in park) while at a stop light disappeared. Feels exactly like an LS should: like nothing is happening. Simply cannot feel the engine running now.

My LS only had 86,000 miles, but at 10 years old, figured they needed replacing.

Eddie

thanks Eddie for your comments, i am saving money :)

btw, what did you replace? engine mounts, tranny mounts, steering rack grommets or all of them?

[originalls]

is there any chance that changing those could lead to that common rack leak?

definitely not

Thanks. I just wanted to be sure that there would not be enough movement to cause seals to shift and bind.

I have been to my local Lexus dealer half a dozen times in the last 2 years on this vibration issue, suggesting they check mounts, but always they come back with - you need new tires. I have now purchased new tires twice - first set feathered in 5-6k miles, and now just bought another set. Vibration is still there. Do dealers not have a clue about the proper condition/life expectancy of mounts and/or the common causes of vibration? I am sick of "it's the tires" as the stock answer. I have come so close to selling my beloved 90 LS - 210 k miles, mint, all records since new - because I am frustrated beyond all reason with the vibration issue and lack of dealer understanding. How they could test drive the car with new tires, say "there's now just a little vibration" and think the problem is solved is beyond me. So....I think I'll take the advice of others on this post and just buy the mounts online and go to an indie shop and take a flyer on it and see what happens - hate to part with a car I think is a joy to drive when right.

[eddielasvegas]

If you've replaced the tranny mount and motor mounts, try replacing the "center support bearing." I found a reference to this causing tough-to-solve vibration problem on a '99 LS 400 on another Lexus forum. I believe it's part of the drive shaft, but not sure where it is or what it looks like.

I'm guessing the above applies to your '90, but I'm not sure given these ideas are directly related to '98-'00 LS 400's.

Good luck,

Eddie

is there any chance that changing those could lead to that common rack leak?

definitely not

Thanks. I just wanted to be sure that there would not be enough movement to cause seals to shift and bind.

I have been to my local Lexus dealer half a dozen times in the last 2 years on this vibration issue, suggesting they check mounts, but always they come back with - you need new tires. I have now purchased new tires twice - first set feathered in 5-6k miles, and now just bought another set. Vibration is still there. Do dealers not have a clue about the proper condition/life expectancy of mounts and/or the common causes of vibration? I am sick of "it's the tires" as the stock answer. I have come so close to selling my beloved 90 LS - 210 k miles, mint, all records since new - because I am frustrated beyond all reason with the vibration issue and lack of dealer understanding. How they could test drive the car with new tires, say "there's now just a little vibration" and think the problem is solved is beyond me. So....I think I'll take the advice of others on this post and just buy the mounts online and go to an indie shop and take a flyer on it and see what happens - hate to part with a car I think is a joy to drive when right.

[Bali26]

is there any chance that changing those could lead to that common rack leak?

definitely not

Thanks. I just wanted to be sure that there would not be enough movement to cause seals to shift and bind.

I have been to my local Lexus dealer half a dozen times in the last 2 years on this vibration issue, suggesting they check mounts, but always they come back with - you need new tires. I have now purchased new tires twice - first set feathered in 5-6k miles, and now just bought another set. Vibration is still there. Do dealers not have a clue about the proper condition/life expectancy of mounts and/or the common causes of vibration? I am sick of "it's the tires" as the stock answer. I have come so close to selling my beloved 90 LS - 210 k miles, mint, all records since new - because I am frustrated beyond all reason with the vibration issue and lack of dealer understanding. How they could test drive the car with new tires, say "there's now just a little vibration" and think the problem is solved is beyond me. So....I think I'll take the advice of others on this post and just buy the mounts online and go to an indie shop and take a flyer on it and see what happens - hate to part with a car I think is a joy to drive when right.

If your mounts have never been replaced, then thats the reason of vibration.

[eatingupblacktop]

Here's a simple test you can do. At idle, place your hand

on the top of the engine, say the intake manifold. Engine

should idle smoothly with no vibrations. Mounts do not

prevent engine vibrations, they prevent vibrations from

being transmitted. If you feel vibrations,, then my guess.

your problem is not solely the mounts. I would check for

dirty plugs or injectors.

[ghenley]

I recently had the motor mounts and transmission mount replaced on my 96 LS400. It runs like new. This was one of the best repairs I've had done.

Greg

[fisher972002]

Yeah,

You'll be happier after replacing them.. Especially in cold weather, they are old they make vibrations.. I used to have a vibration in my door when I pulled out of garage in cold weather.. ALso could feel vibrations in the foot pedal and floor a little bit and shifter..

Replaced tranny mount, old one was still good, didn't help

So had to be engine mounts

1991 LS 400 170K.. No more vib's.. one of hte best fixed on this car next to the rear carrier arm bushings.. Definitely if you aren't sure they have been done, and you feel any vibrations.. I noticed slightly bumping throttle from idle, about 1200 RPM's is when mine vibrated..

No more smooth as silk... Even in dead cold..

Old mounts weren't separated.. They were torn all hte way around about 1/3 of hte way in is all.. they were also a little hard, but not too bad.. But mainly they were torn and you can't see they were torn unless you had them out of hte metal shell ya know...

GL