Auto Choke On New Is250 ?

[Bocabar]

Hi

Has any new IS owner experienced what I presume must be the Automatic Choke staying on for a prolonged time, the engine races and the auto grabs, when placed in drive for 10 Mins or so after start up, it even seems to come on in the recent hot spell we had, on previous cars I could cancel out the auto choke by stabbing on the accelerator a few times, but it doesn't seem to work on the new IS, perhaps this was a feature of the old IS too, I wouldn't know as this is my first Lexus, other than this little niggle, the car has been superb since delivery last November ( pre ordered as I took a test drive in the USA last Oct. so was one of the first )

[Ro1]

I have the same car. The revs are a little higher in the first few minutes, but far from racing. I'd say about 400 - 600 rpm higher.

When you say the auto grabs, do you mean jumpy gear shifts? If so, I haven't noticed this at high or low revs, with hot or cold engine.

[Whoosh]

I have often thought that the revs are quite high from a cold start but it usually settles after 300-400yds. I havn't noticed any grabbing from the gearbox at all.

[alpappy]

No problem with my car Take to have it checked out

alan

[lex-mike]

Hi

Has any new IS owner experienced what I presume must be the Automatic Choke staying on for a prolonged time, the engine races and the auto grabs, when placed in drive for 10 Mins or so after start up, it even seems to come on in the recent hot spell we had, on previous cars I could cancel out the auto choke by stabbing on the accelerator a few times, but it doesn't seem to work on the new IS, perhaps this was a feature of the old IS too, I wouldn't know as this is my first Lexus, other than this little niggle, the car has been superb since delivery last November ( pre ordered as I took a test drive in the USA last Oct. so was one of the first )

My IS250 does the same. From a cold start the engine revs at approx 1500rpm, consequently when you engage drive or reverse the transmission will 'shunt' and the car will lurch slightly unless you have your foot firmly on the brake. The increased revs slowly reduce until the engine reaches working temp at which point the idle rpm is about 600. It has taken a bit of getting used to as my previous car (BMW 5) did not increase the revs regardless of engine temp.

[Tango]

Hi

Has any new IS owner experienced what I presume must be the Automatic Choke staying on for a prolonged time, the engine races and the auto grabs, when placed in drive for 10 Mins or so after start up, it even seems to come on in the recent hot spell we had, on previous cars I could cancel out the auto choke by stabbing on the accelerator a few times, but it doesn't seem to work on the new IS, perhaps this was a feature of the old IS too, I wouldn't know as this is my first Lexus, other than this little niggle, the car has been superb since delivery last November ( pre ordered as I took a test drive in the USA last Oct. so was one of the first )

My SE-L Auto was also one of the first (December). but the auto choke is fine. No indication that the choke over revs, maybe 200-300 rpm higher but no grabbing or pulling.

[Arkanoid]

Hi

Has any new IS owner experienced what I presume must be the Automatic Choke staying on for a prolonged time, the engine races and the auto grabs, when placed in drive for 10 Mins or so after start up, it even seems to come on in the recent hot spell we had, on previous cars I could cancel out the auto choke by stabbing on the accelerator a few times, but it doesn't seem to work on the new IS, perhaps this was a feature of the old IS too, I wouldn't know as this is my first Lexus, other than this little niggle, the car has been superb since delivery last November ( pre ordered as I took a test drive in the USA last Oct. so was one of the first )

My IS250 does the same. From a cold start the engine revs at approx 1500rpm, consequently when you engage drive or reverse the transmission will 'shunt' and the car will lurch slightly unless you have your foot firmly on the brake. The increased revs slowly reduce until the engine reaches working temp at which point the idle rpm is about 600. It has taken a bit of getting used to as my previous car (BMW 5) did not increase the revs regardless of engine temp.

No problems with mine. Engine revs fairly high from start in P. but as soon as put in Drive with foot on the brake revs drop. No lurching.

[alpappy]

Interestingly I have a petrol and the company rusn a diesel The diesel has higher revs when cold than the petrol but settles down quickly the petrol has never revved tht high wehn cold I am sure that the computer can be re set to run lower when cold!

alan

[oldcro]

Tried my IS250 SEL today. Weather was cool, 9 degrees C and on starting in park(obviously) engine was doing 1600rpm. Gear into drive with brake firmly on and the revs dropped to 1000rpm. This is what the car has done from new, and presents no problems. It may affect those with a manual transmission a bit more though.

I suspect that because the engine runs so lean to improve fuel economy, the "automatic choke" enriches the engine more and for longer than old engines use to.

oldun

[Carlos B]

I think the engine revs stay up whilst cold to warm the engine up quicker so that emissions will be reduced.

My car revs at about 1300 for the first few minutes and then settles down to about 600.

[swamprat96]

Mustn't get cold enough in OZ- haven't noticed this at all

[Tel]

Cold start with handbrake ON, revs @ 1600 which falls to 1000rpm when reverse is engaged then idles @ 800rpm very shortly thereafter.No drive-line shunt whatsoever But I do always cold-start & engage drive with the "hand-brake" ON & ,in winter, will idle for c.20secs before engaging drive.

TEL

[Steve ( West Mids )]

As above, cold start @ 1600 rpm, engage reverse and the revs fall to 800. No jerking, clunking or anything. November 2005 IS250 SE Auto approx. 8000 miles.