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j_jazzy777

High Fuel Consumption

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Is the O2 Sensor the thing mounted next to the air filter and near the throttle body? Looks easy enough to change if it is - where can you get one from?

Mine's coming up on 50k miles, so I might replace the plugs, too. To do this, I presume you need to remove the airbox? How are the coilpacks attached to the plugs?

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i filled up last night with the good stuff from shell

i did 260 miles on the last tank...

how do you check/clean the O2 sensors

your not confusing your manual with an auto are you?

Just thinking if you tried using the rest of the gears you might get better consumption?

that whould explain why cars keep over taking me...

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For more information regarding the O2 sensors see the GS300 forum (page 3 i think) title 'Important advice for those who have a higher mileage GS300'. Not sure where the O2 sensors are on the IS, surely some other IS members should know.

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Thanks for all the pointers. I'll have to investigate these.

Noticed from going back through the service history that the air filter was only changed fairly recently. However, I'm wondering whether they didn't fit it properly and this is a possible cause?

Unless anyone has any better advice, I'm gonna try the following-

1. Set the wheels air pressure to the correct psi

2. Reset the ECU.

(Anyone any advice on this because I have heard different things- is it better to drive harder or slower after resetting it?)

3. Getting a full geometry on the wheels on the 24th- something the car inspector recommended and notable within the car's history about steering issues.

4. Failing all that, book it in with the garage to replace the plugs for Denso's and change of 02 sensor.

5. Failing that, sell it on and buy...something else. Maybe another Alfa?? Er...then again, maybe not.

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Ive just filled up and around town heavy right foot miles im getting about 17.5 mpg I think i need to start driving a bit more econmically

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Ive just filled up and around town heavy right foot miles im getting about 17.5 mpg I think i need to start driving a bit more econmically

Wish I had that luxury! I'm pootling around and petrol is just burning away- somwhere! I noticed clouds of white exhaust coming out the back on occasion- especially in the morning when first run, but everyone assures me this is normal.

Isn't that unburnt petrol pouring out of my exhaust?

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white smoke is nothing more than water or condensation perfectly normal especially first thing in the morning. If it continues check to make sure your water/coolent levels are ok as it could be leaking a little but I dont think it would cause low mpg

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I get clouds of white smoke, especially when it's cold. I was sat in traffic for about 30 mins this morning and it didn't go away, until I hit a stretch of dual carriageway and could put my foot down. That always seems to cure it!

I'm used to a diesel, so the first month or so seeing lots of white smoke had me worried!

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Thanks for all the pointers. I'll have to investigate these.

Noticed from going back through the service history that the air filter was only changed fairly recently. However, I'm wondering whether they didn't fit it properly and this is a possible cause?

Unless anyone has any better advice, I'm gonna try the following-

1. Set the wheels air pressure to the correct psi

2. Reset the ECU.

(Anyone any advice on this because I have heard different things- is it better to drive harder or slower after resetting it?)

3. Getting a full geometry on the wheels on the 24th- something the car inspector recommended and notable within the car's history about steering issues.

4. Failing all that, book it in with the garage to replace the plugs for Denso's and change of 02 sensor.

5. Failing that, sell it on and buy...something else. Maybe another Alfa?? Er...then again, maybe not.

From my past experience after getting a full geometry my fuel consumption was about the same.

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My advice is check the air filter. If it's clogged and full of crud it will choke your engine and result in poor economy. Tyre pressures too are worth checking athough it wont make a massive difference.

I dunno if replacing the O2 sensor will make any diff. It basically is like any other electrical component, its either good or bad working or not. If they weren't you would know about it (your car would run like a lawnmower)

Same with the geometery. If your tyres are wearing evenly then it is not going to do much either.

Could possibly be the catalytic converter but you need to take it to the dealer and see if there are any fault codes being thown up in the ECU.

Believe me I don't like the dealer any more than you lot but there are times when you need to call upon his expertise. I used to work as a Sevice advisor for two Sport/Luxury dealers here and in the USA and it never failed to amaze me the amount of money people would throw (in the wrong direction) at their car rather than pay for one hour's labour (Thats the usual diagnosis/inspection rate although if you buy the repair then make sure it is absorbed into the entire labour time for the job)

It's worth a go - plus you get a free car wash!

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Hi everyone,

I just can't beleive how some of the guys on the forum say they get 350-400 on a full tank. I think this is nothing short og divine intervention.

I drive like i'm driving HRH Queen Lizzie round & the very best I've ever got is 250 & thats motorway driving too!!!

The lex drinks like petrol's going outta fashion, more than any other 2.0 in its class in fact (apart from the jap t/c models of course)

I had a sticking caliper(s) - got those changed yesterday along with new discs/pads & lower ball joints. I'm hoping the caliper situation will help consumption but i'm not holding my breath.

I've checked my air filter all is good, another thing is that I can't beleive that changing plugs is whole heartedly responsible for poor consumption.

I hope you sort it out bruv as 14mpg is real bad. In fact its just 1mpg more than my brother's old bmw v12!!!

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The problem with getting the fault codes checked is that some junior mechanic will do just that and in some cases will simply tell you that there are no fault codes found and so there is nothing wrong....Fault codes are limited in what they can tell you...there are plenty of faults that won't generate a fault code.

For example, is a sooted up and defective lambda (O2) sensor (fitted in the exaust) a symptom of a faulty lambda sensor or a faulty engine temperature sensor? Eventually you will get a fault code saying that the lambda sensor is faulty but the true cause may be that the engine temperature sensor has failed (Many cars will not give a fault code for a faulty temp sensor as any temperature that it may report to the ECU could be a valid temperature (-50 if you live in Siberia or + 50 if you live in Dubai))

From this example we can see that we could have a situation where there may be either no fault code or a code for a faulty lambda which has been caused by a faulty engine temperature sensor which is causing the ECU to think that the engine is cold and so is overfuelling due to the car being constantly in its cold start mode (on choke)

This is just what I have picked up from my experience with other cars and may not be valid to the IS200 but it may be worth checking out..

If a lambda sensor is sooted up then it can be cleaned by removing it from the exhaust and heating up gently with a blowtorch to burn off all the soot...If it is genuinely faulty then you will need a new one.

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Hi everyone,

I just can't beleive how some of the guys on the forum say they get 350-400 on a full tank. I think this is nothing short og divine intervention.

I drive like i'm driving HRH Queen Lizzie round & the very best I've ever got is 250 & thats motorway driving too!!!

The lex drinks like petrol's going outta fashion, more than any other 2.0 in its class in fact (apart from the jap t/c models of course)

I had a sticking caliper(s) - got those changed yesterday along with new discs/pads & lower ball joints. I'm hoping the caliper situation will help consumption but i'm not holding my breath.

I've checked my air filter all is good, another thing is that I can't beleive that changing plugs is whole heartedly responsible for poor consumption.

I hope you sort it out bruv as 14mpg is real bad. In fact its just 1mpg more than my brother's old bmw v12!!!

Can relate. I read that your 02 sensor should be changed every 20k miles anyway. Mines got 28k miles on the clock.

The other possibility is that in the last service, the work was undertaken by a garage that are not Lexus accredited, so the chances are that they fiddled something to break down later anyway. If there is one thing I have learned in being a car owner is- it is worth taking it to the specialists, bceause the job done improperly can cost you more in the long run and also to find a recommended dealership, not just the closest. There is no indication that the spark plugs have been changed in the service history and I know that they are supposed to last for 60k miles minimum.

Maybe I need to just step out in faith and take it to the Lexus garage. Anyone got any particular recommendations? I live in Watford, Herts. I'm considering Hatfield. :duh:

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Hi everyone,

I just can't beleive how some of the guys on the forum say they get 350-400 on a full tank. I think this is nothing short og divine intervention.

I drive like i'm driving HRH Queen Lizzie round & the very best I've ever got is 250 & thats motorway driving too!!!

The lex drinks like petrol's going outta fashion, more than any other 2.0 in its class in fact (apart from the jap t/c models of course)

I had a sticking caliper(s) - got those changed yesterday along with new discs/pads & lower ball joints. I'm hoping the caliper situation will help consumption but i'm not holding my breath.

I've checked my air filter all is good, another thing is that I can't beleive that changing plugs is whole heartedly responsible for poor consumption.

I hope you sort it out bruv as 14mpg is real bad. In fact its just 1mpg more than my brother's old bmw v12!!!

Can relate. I read that your 02 sensor should be changed every 20k miles anyway. Mines got 28k miles on the clock.

The other possibility is that in the last service, the work was undertaken by a garage that are not Lexus accredited, so the chances are that they fiddled something to break down later anyway. If there is one thing I have learned in being a car owner is- it is worth taking it to the specialists, bceause the job done improperly can cost you more in the long run and also to find a recommended dealership, not just the closest. There is no indication that the spark plugs have been changed in the service history and I know that they are supposed to last for 60k miles minimum.

Maybe I need to just step out in faith and take it to the Lexus garage. Anyone got any particular recommendations? I live in Watford, Herts. I'm considering Hatfield. :duh:

Bruv i'm not sure when the O2 sensors need replacing. I'm more than sure that an o2 sensor should last more than 20K.

Maybe one of the brothers on the forum can shed some light.

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probably. Were your miles stop start or motorway miles though as most of mine are stop start traffic miles. Also mine was picked up from a lex dealer who did a full 30,000 mile service on it so all that needed changing and checked should have been

360 was on the motorway for most of the journey.

I get circa 400 miles normaly and that can be through town but were pretty rural round here so the town isn't that big and its not full of cars bumper to bumper all the time.

I am concious of the MPG needle and I do watch it. all I do is take my time don't eraticly drive as in foot on excelerator and then brake and back again.

To be fair though, as much as I love the Lex it's not the most economical petrol engine, straight 6's never were, really smoth and dead quiet though. I'd love the BMW 2.5d engin dropping in the lex as I don't really like the 3 series around the same price bracket as my Lex as there basic and common.

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j_jazzy777 Where you having your geo done?

Just spotted this.

At STS (Wheels in Motion) in Watford. They are famous within the Lexus owners club forum anyway, but they also came highly recommended by the car inspector. Having read reviews, no-one has a bad thing to say about them.

http://www.wheels-inmotion.co.uk/

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Took the bull by the horns so to speak and booked it into Lexus Hatfield although I read somewhere that the courtesy car was only an additional £10, but they have said its £15 per day!!

This sounds a bit much to me. What does anyone else think??

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i wont be up thier till 11am got to drive up from kent.... :D

Yeh, I noticed that you live in Kent from your profile. Its spooky- me and the gf were thinking of moving to Ashford. Following the top ten places to live in Britain on TV last yr, we went on a 5 day tour around the various "golden spots" and the place we really liked was Ashford- just the right mix of quiet, but not too quiet, and a really pleasant feel. Just couldn't get work down there, so instead we moved to Grotford ("Watford"- if you dont live here!)

We now want to move to Manchester, but haven't found work there yet.

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I really shouldn't trust ppl.

A Lexus service was done at 72,000 and it now has 75,000

i took the filter out to have a look and.... it was covered in black crap, dead fly and other things....

i'm going to replace it with a k&n today but i can't belive that they didn't change it

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Hi everyone,

I just can't beleive how some of the guys on the forum say they get 350-400 on a full tank. I think this is nothing short og divine intervention.

I drive like i'm driving HRH Queen Lizzie round & the very best I've ever got is 250 & thats motorway driving too!!!

The lex drinks like petrol's going outta fashion, more than any other 2.0 in its class in fact (apart from the jap t/c models of course)

I had a sticking caliper(s) - got those changed yesterday along with new discs/pads & lower ball joints. I'm hoping the caliper situation will help consumption but i'm not holding my breath.

I've checked my air filter all is good, another thing is that I can't beleive that changing plugs is whole heartedly responsible for poor consumption.

I hope you sort it out bruv as 14mpg is real bad. In fact its just 1mpg more than my brother's old bmw v12!!!

I as well do not know how these guys get such mileage. I recently got 15.04mpg and that was soon after my 40,000 mile service. Previously at my 30,000 when I complained to the dealer about fuel consumption they changed the air filter with no effect whatsoever. Granted I do mostly short journeys ie. under 10 miles but it seems to be a affliction of automatics. When I drove manual Honda Preludes even when the car was over 10 years old I was still getting above what the manufacturer claimed for urban driving.

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I really shouldn't trust ppl.

A Lexus service was done at 72,000 and it now has 75,000

i took the filter out to have a look and.... it was covered in black crap, dead fly and other things....

i'm going to replace it with a k&n today but i can't belive that they didn't change it

I understand the pain Y2K.. as the car is with the Lexus garage at the moment and I stated two issues to resolve-

1. the fuel consumption- main concern!

2. knocking on steering- secondary concern.

So, yesterday they replaced the front two shock absorbers costing £600! Then they wanted me to pick up the car- they hadn't even looked at the fuel consumption. After insisting that I was not going to pick it up until everything was done, I was then passed to a "technician" who tried to fob me off, and whom I had to educate about ECU reset!!!

I wrote a list of things for them to check and they have done none of it. I'm sure they are keen to get their IS220d back, but then I'm paying £15 a day for the "courtesy"

I always thought Lexus dealers were reliable- not so far though!

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