Idle Rpm Unstable

[Tadzio]

Avensis 2.0 99

Hi there,

On idle running I have noticed that sometimes RPM is unstable. Sometimes it's almost 1000 sometimes about 800 (in the same conditions: without A/C, lights,...)

Is this normal? During 60.000km inspection sparking plugs were changed. Could it be the reason?

[Oli]

does it move between 800 - 1000 while running or sometimes go to 800rpm and other times 1000rpm?

[Tadzio]

It is slowly fluctuating and sometimes when rpm drops below 800 unpleasant vibrations appears.

[Unity Jon]

sounds like a vacuum problem, possibly a split or loose hose.

[Oli]

i didn't have a clue. Jon's reply sounds good though

[RichB]

Try a decent service, make sure the plugs that go in are gapped correctly.

Do these engines have Idle control valves? Might need cleaning.