Vibration at Idle

[Petsounds]

Hi guys, my first post on the forum, but long time lurker.

I have a 1996 Vs series 2. When i first start the car i have a noticeable vibration through the car. After 10 mins of driving totally disappears. Also does not happen when i start the car when it is warm, or been driven in the last couple of hours. Any ideas on what it could be?

I have read alot of posts and thought it might be engine mounts, but wouldn't this happen all the time, and not disappear?

Many thanks in advance

[hako]

Welcome to the forum - re the vibration, my first thought would be simply that the revs are a bit low at idle and once it warm up the revs also pick up a bit and it smooths out. Mine does this at the moment . The idle is controlled by the IAC (idle air control) and the throttle body both which can be cleaned as they do glug up which then affects your idle speed. There is also a 'base idle speed' adjustment but this is rarely touched as it can throw the IAC and ECU out of whack.
The idle should be 800rpm in Neutral or Park and 700rpm in Drive or Reverse.....both plus or minus 50rpm....hot or cold. If it's much below those figures when cold, then that will be the cause of the vibration....simply low revs.
I'm in no real hurry to clean my IAC and TB as I can live with the slow idle when cold but if it's bugging you then I'd first clean them - the cost will be under $10 as all you need is a can of throttle body cleaner. There is a how-to in that section of this forum Good Luck.

[Muzz the kiwi]

Hi i had same problem with my vs ute when i started the engine it would run smooth but as soon as i put it into drive ,at this stage i am
still stationary it would vibrate quiet bad ,and as soon as you take off it would run smooth . I replaced my engine mounts and solved
my problem , this is another option you can look at as well. Good luck

[Petsounds]

Hey guys thanks for the replies.

My revs seem to sit just under halfway between 0 and 1. I would guess around 300rpm and then come up to about 500 rpm at idle. I recently had the throttle body cleaned and base idle looked at by my mechanic. Seemed to be ok for a week, and then back to vibrations. I will try cleaning out the IAC and see if this helps.

If it was engine mounts, wouldn't the vibration occur all the time?

What other things should i look at?

[hako]

Check the throttle cable very carefully for stiffness....sometime they can fray just inside the outer cable and jam although this is usually the cause of a high idle but I'd check it anyway because it may have been sticking when the base idle was checked making that check suspect. Bad engine mounts will cause a vibration at all revs..hot or cold but usually it's metal to metal from the mount sagging or shearing. From you description of the idle speed it seems to be about 3-600rpm which is very low....fix the idle speed and my bet is you''ll fix the vibration. Check for vacuum leaks as well especially around the TB and IAC - hoses can appear OK but be split or blocked internally.
It's all a process of elimination....frustratingly so!

[accentstencil]

Worn engine mounts won't necessarily cause a vibration all the time. Just last week someone had a problem where they had a vibration only at idle and I suggested he check the mounts, he did and found they were both split. He replaced them and no more vibration. So it would be worth your while to check them anyway.

[hako]

Worn engine mounts won't necessarily cause a vibration all the time. Just last week someone had a problem where they had a vibration only at idle and I suggested he check the mounts, he did and found they were both split. He replaced them and no more vibration. So it would be worth your while to check them anyway.

Fair enough....but I wouldn't think worn mounts would cause the idle to be 3-500rpm at which speed the engine will basically shake because it's idling too slow.

[accentstencil]

Fair enough....but I wouldn't think worn mounts would cause the idle to be 3-500rpm at which speed the engine will basically shake because it's idling too slow.

No it wouldn't cause the low idle but I was only referring to the vibration, I missed the low idle bit. I just realised it was Muzz the kiwi in reply 3 I was talking about earlier. I really should have read the entire thread but it's late and I'm tired.

[Muzz the kiwi]

Hi gentleman , I,ll put my 2 cents worth in again i can,t stress enough my vibration was only when i put it in drive with my foot on
the brakes , and it did not vibrate all the time , Good luck