Automatic Choke

[Burroo 67]

Hi Guys,

Had the IS 220d for 9 days now and loving it, just trying to get used to the different driving style after having a Hionda Civic 2.2 (fast wee car).

I find that the automatic choke stays on for ages, even when the car has 'heated up'. I am talking about constant running over a period of 20 minutes or so and it still idles at 12000RPM!!

Spoke to my mechanic guy who says he can't find any problems with it ("computer says No") - so thought I'd ask the experts. Is this a quirk with the 220D or should I take it to a Lezus specialist??

[johnatg]

No such thing as a choke these days, especially with a diesel. Idle speed is entirely up to amount of fuel being injected. I'd say you've possibly got an injector problem - one (at least, possibly the 5th one) injecting too much? Might be the control ecu (unlikely) or a temperature sensor (more likely).

[Burroo 67]

John,

Many thanks for the response and please excuse my ignorance re all things mechanical (thank the lord for these Forums). Sound like it could be an expensive repair.....I'll speak to the guy who does my cars (doubt if the showroom will be interested as I'd have to drive 268 miles to get there and the same back so they know i will not be doing that as we'd probably be talking an overnight stay as well!!).

Cheers mate

Burroo

[daddypatches]

Hi, have you got the air con on? My car idles around 1200 with air con on, turn it off and it drops to around 800.

The 220d often gets a lot of bad press on this forum due to a number of well known problems around carbon build up so worth checking put the following:

• there's a link on you tube to cleaning the egr valve - if this gets clogged, it causes a whole raft of problems. This may look daunting but relatively straight forward (I just about know where the oil goes and I can do it!)
• Buy yourself some BG44 and archoil AR6200 to add to the fuel and keep the engine (relatively) clean

That aside, enjoy. Its a great car.

[Steve_M]

It's more than likely the aircon. Try stating it up from cold and immediately turning off the aircon, should reduce the idle speed to around 7-800 (ish).

[Burroo 67]

Many thanks for the responses guys.

It's nowt to do with the aircon - I live in Scotland remember so use aircon about twice a year!!. I talked to some people about the AR additives as suggested by Carl and it seems to be a sound suggestion, even my mechanic states it might not be a bad thing. If that doesn't work I've to run it by him a week on Tuesday and he'll do a full check on it as he says that the diagnostic could show that the temp sensor is working as technically it is??

Dropped to 800 on the way home so it DOES perform eventually the way it should. I'll post when I get it sorted (says he hopefully!!)

Thanks again, it's good to know there is sound advice out there.....

[normski2]

Its worth checking the EGR. If its a bit full of crud the crud can prevent the piston opening and closing, in particular, properly into its seating. This can then trick the engine into sensing a fuel mix anomaly and higher revs may well result.

Using Bg44K and AR6200 does help with a cleaner burn and aids cleaning the top end. When I had my 220d i used a can of BG every 8,000 miles or so, and 5ml to 50 litres of fuel at each fill up. It certainly seemed better with it.

[phil_1985]

I have a toyota with the same engine - this 1200rpm idling sounds normal - when others have said air con i think they mean climate control.

Having the heaters on 21 degress or above with an ambient temp of 0 degrees or lower the engine will idle at 1200rpm. As above but ambient temp between 0 and 10 degrees it will idle at 1000rpm.

The engine will idle like this until the engine has reached FULL operating temp.

The climate control (well heaters) utilise a PTC heater for UK spec cars - this requires (in toyota vehicles - i imagine lexus will be the same) 3 x 30amp relays as they draw a lot of electric!

I assume this is why the engine increases it's idle when these PTC heaters are active.

[Burroo 67]

Right guiys,

I have now put a bottle of AR6400 -D in the tank and filled up with fuel, so need to wait and see if this does the trick. What I did notice this morning on my way in to work was that the car interior was warm as toast and the temp guage was about 1/4 way up - this is after driving for 10-15 mins with three stops at traffic lights - and the car was still idling at 1200. When I approached a set of lights at red I knocked the car into neutral and coasted - the revs were at 800-900, but as soon as I came to a complete halt they increased to 1200?? I tried this a few more times (lots of lights on way into work) and the same thing happened every time?

Any new ideas on why this should be, I believe there muist be a motion sensor in the car as the windscreen wiperfunction adjusts when the car comes to a complete stop, but idling speed???

Many thanks.

Burroo

[Steve_M]

Listen to Phil_1985. myine does this no matter what additives I use and irrespective of the outside temperature or the state of cleanliness of the egr valve. the Only thing I have found to lower the idle speed until the engine is fully up to temp is turning off thr climate control.

[Burroo 67]

will try turning off the climate control tomorrow, cheers.

[Burroo 67]

Epilogue....

Was told by showroom I bought the car from (in Sheffield) to run car by Arnold Clark TOYOTA in Paisley where a very knowledgable Service Manager confirmed what a couple of you guys had been saying. The climate control and aircon use a lot of electricity and the higher revs is the car's way of handling this, making sure the Battery has enough juice to run things until the engine reaches full running temp. On the way into work this morning I turned off the climate control and the car idled at 800RPM. Stopped at the lights I switched it back on and the revs immediately rose to 1200 - problem (or what I believed to be a problem) solved and I suppose the £60+ I spent on fuel additives can only do the car some good.

Many thanks again to all contributors, really looking forward to many happy years of driving with my new IS220d - especially the drive to Cornwall in July - comfort all the way.....

Cheers for now guys

Burroo

PS: - I'll stick a pic of the car on the site once I get my own plates on it to finish it off...