On every startup the revs are at 2100 rpms

[chana100red]

Hey Guys,

Recently purchased a newer 2009 Jan Toyota Avensis bu tthe old shape.  Completed 35,000 miles with last service history around 2017.  Will be carrying out a mini service very soon.

Noticed that every time the car is started up the idle is always over 2000 RPMS and then after 30-40 secs goes down.

Not sure if there is a problem or a sign of something about to go wrong.   A bit concerned although the mixture smells a bit too rich.   

Does anyone know or experienced a simialr issue.

Any thoughts on this as I really would really like to know as my previous 2004 Avensis never did this.....

 

[mikejbry]

Most petrol vehicles, motorbikes, cars etc, run a higher idle as they warm up. Is it not that?

 

Alternatively I'd check for a vacuum leak, split hose or similar. Do the revs hang in the same way while you are driving? My Mondeo did this. It had a split PCV hose, that caused revs to hang before dropping down to normal levels.

 

Also on the opposite side it could be fuel related, does it smoke at all?

[chana100red]

Hi,

 

The idle does go down after a minute.  it drives ok.  Thankfully no smoke at all.  It has only done 35,000 genuine verified miles.   Toyota dealer has verified this and all seems fine.

I was thinking perhaps the MAF sensor might need cleaning, although I am looking to change the spark plugs, filters and oil seems clear at this present moment.

Certainly a strange one but cant get my head round this one!

My 2004 Avensis did NOT over rev as much as this one does.

 

[TonyHSD]

There is something wrong indeed. , perhaps cleaning tlc etc. 

[T27driver]

I’d check the air filter first. 

[Konrad C]

It's normal. I own the 1.8 Valvematic Tourer and the engine when cold starts with a high rpm idle, then settles down to a normal low rpm as fast as possible. It also depends on temperature. When really cold, this high idle helps the engine to warm up quicker, which helps everything like the emissions system and heating be more affective.

[chana100red]

The cold start I can understand but not at 4pm when it was sunny outside today in SOuth East London.  It revved to 2300rpms, very unusual behaviour.  I had two Avensis beofre this one and none of them revved this rediculousy high for a minute.  Each time the car is started it over revs and clearly there is an issue.

 

I simply do not know where to start....

[mikejbry]

So once the car is up to temperature you don't notice the revs climb again while driving or coming to a stop?

[chana100red]

Once the car settles down after a minute the revs does not climb up while driving or coming to a stop.  I certainly follow a few advice given earlier and I plan to change the spark plugs, air filter, cabin filter and clean thr MAF sensor if required.

The oil is quite clear and NOT black in colour so seems like someone had done a quick oil change.

 

I also recorded miles to the full tank and I got total 380 miles on full tank.  I thought I would get a bit more than that and was expecting around 430 miles for this type of car.  I do constant motorway mileage of around 13 miles each way so the car is getting a daily good run.

[avensis_2018]

you need to do 4 things:

1. change the spark plugs

2. add additive to the fuel system, 2 on half tank or 4 on full tank.

3. clean your throttle.

4. clean the air filter sensor

you can diy all.

[m456an]

I would do them 4 things. Though according to my Yaris Haynes book you can simply vacuum the air filter. Also use OEM spark plugs, I use twin tip. 

Though I had a very loud idle every 2 weeks which was fixed by cleaning the pcv.

Copy and paste:

The PCV valve regulates how much vacuum can pull through the crankcase. It's hooked into the intake - when the vacuum is high at idle, the PCV valve stops most of that vacuum. As vacuum drops with an increase in RPM, The PCV valve opens, to allow a higher volume of gasses and pressure to be pulled into the intake.

You can buy a throttle intake cleaner spray. If you use too much it does not matter. The car will not start, but it does not matter as it will start at the second attempt.

[chana100red]

Wow guys, thanks for all the advice and tips for you and others have took you're valuable time to help.  I really was stuck until now.

I will certainly do all those fixes and am sure it will be running far better.  I am a bit of a DIY in cars and will get help from a member of the family.  

Will let you guys know the outsome of this repair shortly.

cheers

 

[Gerg]

I have never owned an Avensis, but, In addition to the above answers, and as Konrad alluded to, the Euro 4 emissions regulations came into force for new petrol cars in 2005/2006.

It would seem (from just occasionally looking under bonnets!) that this heralded the introduction of throttle-by-wire in a major fashion, presumably to meet these regs.

I had two petrol Mazdas from that era, and they both did exactly what your car does.  I have a strong suspicion that the high revs are to get the catalyst up to temperature as soon as practical, again to meets the new, tougher regs.

Given that the catalyst needs to operate at 600 degrees for full efficiency, and only has engine exhaust gas to heat it up to the correct temperature, the revving seems more easily explained. The engine needs to produce a volume of hot gas, and quickly.

The Mazdas were quite bad with the over-revving, as the catalyst was a long way down the exhaust manifold (relatively). This design does allow for a more fuel-efficient manifold with longer, seperate, exhaust header pipes prior to the cat., which then allows for the individual exhaust pressure pulses to be used to good effect before they join up into one pipe.

Especially with the electronic throttle plate mentioned above (drive-by-wire), I would have thought the car had total, tight control of the cold start revs, and this revving was just part of the engine ECU map. But owners will know best of all if this is 'normal'!

Happy to be corrected on any of this, of course!

[Konrad C]

It may not be related, but look at my post regarding fake spark plugs, noting what to look for. 

Only if the spark plugs were obtained on eBay. My fake set caused weird idling with the engine suddenly revving to over 2000, as though I pressed the accelerator pedal, even though my foot was not touching the pedal! There were no faults until the EML came on, that was diagnosed as misfire. So check the spark plugs.   

[chana100red]

After changing/replacing the filters, spark plugs (Bosch in this case) cleaned the MAF sensor, throttle sensor seemed to have reduced the high revs down to 30 secs and before it was revving extremely high.  After the changes it does not rev as high as before and seems like it is better.

If there is anythign else i could do to make even better after applying all those fixes then I welcome any advice.  If you think I should leave it alone then the good enough for me.  The car is behaving well no issues.  I get 36mpg at the moment on motorway and in town.

Full tank range is 380 miles.

[mikejbry]

I'd leave it, it's a petrol so will idle high while it warms up.

I'd just start it, give it a few seconds to circulate the oil and get moving. It will warm up quicker while actually being driven, and the revs will settle to normal levels.

[mikejbry]

One thing I hate about our Avensis, aside from being awfully unreliable. Is the small fuel tank, really wish they equipped this large motorway friendly car with a 70L tank. 

 

Your mpg is good though I'd say. My 2.0 zetec Mondeo would get 32mpg (measured at the pump. Not onboard computer), mostly motorway miles.

[Konrad C]

5 hours ago, chana100red said:

After changing/replacing the filters, spark plugs (Bosch in this case) cleaned the MAF sensor, throttle sensor seemed to have reduced the high revs down to 30 secs and before it was revving extremely high.  After the changes it does not rev as high as before and seems like it is better.

If there is anythign else i could do to make even better after applying all those fixes then I welcome any advice.  If you think I should leave it alone then the good enough for me.  The car is behaving well no issues.  I get 36mpg at the moment on motorway and in town.

Full tank range is 380 miles.

So long as all the parts are genuine and come from a trusted source, you should be fine. If from eBay, it must be from an official seller like a known Toyota Garage who also uses eBay. There is one eBay seller where I got the fake spark plugs from, still trading and based in South London. 
Overall, don't throw money at the parts cannon. If I am correct, your car is the last of the T25 1.8 1ZZ engine, not the T27 Valvematic. I am sure that Toyota may have made slight improvements to the engine and ECU. This will include meeting emission and economy requirements, hence the need to reach operating temperature quickly. 

As I said above, your car should be fine. 

[chana100red]

Thanks Guys for your guidance and advice, very valuable and getting the right help is really important.  I will certainly think twice about putting fake/non genuine parts like it did with my previous one.  Cheers Konrad.

As I don't think I will ever reach 420-450 miles to the tank I will leave it alone and service it regulary since I do motorway miles to work and back.  Approx 19 miles each way.

Cheers all!

[chana100red]

On 9/29/2023 at 3:40 AM, avensis_2018 said:

you need to do 4 things:

1. change the spark plugs

2. add additive to the fuel system, 2 on half tank or 4 on full tank.

3. clean your throttle.

4. clean the air filter sensor

you can diy all.

I bought and cleaned out the sensors as listed in your comment and worked a treat, many thanks!