What is your cars warm idle speed?

[Kind Panda]

If you have a 2003 - 2009 Avensis 1.8 VVTi petrol - could you please post your warm RPM idle speed? 

Many thanks

[Devon Aygo]

Toyota specifies 600-700 rpm on a fully warmed engine with no additional load e.g lights, heaters, AC

[Konrad C]

I agree with Devon Aygo. When warm and no load like lights/heater/air-con, the idle is in the 600-700 rpm range. Both my old Mk1 7A-FE and current 1.8 Valvematic idle the same. So the VVTi between the engines mentions may or may not match these figures.

On cold start-up, the peak revs are up to 2000 rpm during the warm up period.

[fastbob72]

From cold,and I'm starting to feel it getting COLD when I head to work around 3.45-4.00 am just now, my 2002 1.8 1ZZ-FE vvt-i idles around 1800-2000 rpm until the engines begins to warm up properly.

At normal operating temperature the engine idles 600-650 rpm with that normal inconsistent way that all modern engines do.

You know the way I mean where it idles around 600-650 rpm rising and falling between that rpm range sometimes noticeably other times less so but that is actually a result of modern integrated engine management systems which almost all petrol engine cars have used since 1992.There were some with eco carbs for a few years but as soon as the catalytic converter became mandatory the computerised fuel/emissions system was the most practical route to take which did away with idle screws/mixture screws and the idle speed being controlled physically by the throttle plate being slightly open.

Nowadays there's an idle control valve and/or a stepper motor opening and closing an air channel that bypasses the fully shut off throttle plate in the throttle body.

As the fuel and timing is directly controlled by the ecu, mostly based on the output of your O2 sensors (of which we have 3 on the 1ZZ-FE. 2 pre the precats in the exhaust manifold and one after the main cat sort of level with the front seats) which is constantly switching rich/lean so the ECU is constantly correcting the air/fuel mix and the ignition timing every so slightly to compensate hence that sometimes unsteady fluctuating idle speed.

If it's sitting basically reasonably steadying between 600-700 rpm when up to temp then that's perfectly fine :)

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[Aidsy1]

Mine is usually sitting about 800 rpm. However as people are talking about it fluctuating, mine fluctuates a lot, almost as if its about to stall then kicks back up, will do this a few times, usually after about 10-15 mins of driving then stopping. Has also been known to increase the revs by itself at standstill (when warm) up to about 1500, then idle and repeat. Is this the evap purge causing this? (first petrol car others have all been diesel).

[fastbob72]

Mine is usually sitting about 800 rpm. However as people are talking about it fluctuating, mine fluctuates a lot, almost as if its about to stall then kicks back up, will do this a few times, usually after about 10-15 mins of driving then stopping. Has also been known to increase the revs by itself at standstill (when warm) up to about 1500, then idle and repeat. Is this the evap purge causing this? (first petrol car others have all been diesel).

The evaporate purge shouldn't operate either when the engine is cold or idling.It basically stores petrol fumes stopping them from leaking to the atmosphere then under load, usual heavy or full throttle feeds them into the intake to be burnt with the air fuel mix. Obviously that will richer the mixture momentarily which is why it only purges under load or full throttle where the AF ratio is richer anyway and probably gone into open loop.

It could be a fault in the system.It depends more on the age of the car, which engine etc. Up to mid 2000 the evaporate was controlled by a bi- metallic vacuum switch after that it was by a VSV and ecu controlled.

The fluctuating idle speed is a feature of computer controlled petrol engines,some seem to be more pronounced than others.

Also a small vaccum leak somewhere in the intake system, around the throttle body, inlet manifold, VSV, evaporate purged or even the PCV valve or any or the vaccum hoses between any of these systems could cause an overly fluctuating or erratic idle.

Dare I say it, the old favourite is equally as likely and that's an ignition issue.Old or badly gapped spark plugs being a likely candidate or a faulty HTC lead/coil pack.

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