Potential fix for is220d, white smoke, smells of diesel, poor mpg,

[smutts]

Just a potential FIX for you bashing your head against this particular wall,

The problem, a 2008 is220d, 110k miles, with embarrassing quantities of white smoke from exhaust that smells of diesel fuel.

My parents car has been smoking like a pig for the last few months,

Diagnosis....
Garage condemmed the DPF and replaced it..................Still smokes.
Garage says "just keep driving it, the smoke will soon stop"............It didn't
Garage says "er, drive it some more"...................Still smokes.
Garage yanks the injectors and send them off to be tested, by people who are not idiots..................non idiots send them back with the verdict, injectors are perfect...........................Still smokes.
Garage now say they are sure it is the turbo which will need replacing...................At which point I get involved and rescue the car.

No sign of misfire, compressions good, no play on the supposedly fragged turbo, no headgasket doom.

Not trusting the fifth injector, I unclipped the fuel line and plugged it by clipping another injector on it.

Went for a drive, white smoke gone! So confirming fifth injector misbehaviour.

Changed the fifth injector, a total git of a job............Smokes, Argh!

So it is the ECU telling the fifth injector to keep on squirting.

Techstream turns up from eBay, so plug it in.

The dpf pressure values are all over the shop, so tee in a magnehelic guage, which disagrees with the values from the software.

Wiggle wiring, AHA! Gotcha! Pressure values in the software change in sympathy.

So I remade the wiring from dpf sensor to the ECU and then got good values for the dpf sensor pressure.

The ECU "learns" whilst you drive, but the corrupt dpf pressure data had totally confused it. Unplug car Battery for ten minutes, reconnect, ECU starts to relearn with good data. Relearn the window winders by driving them for a couple of seconds against their stops at each door switch.

AND THE SMOKE STOPPED! and mpg has gone up from 25mpg imp to 40+mpg imp.

The magnehelic gauge reads 5kPa (20 inches water gauge) when regeneration of the DPF now starts.

So to recap, check the DPF pressure sensor to ECU wiring carefully before spending lots of money on the garage partswap goosechase.


Good luck on what is a fantastic car.

Warning!!!!!!!!!!!!

! I only disconnected the fith injector for long enough for diagnosis, if it is disabled for too long, the DPF will probably clog up! I only disconnected it for 20 miles.

Edited August 22, 2016 by smutts
Clarification

[Shahpor]

Wow, that is some seriously impressive investigation you have done there.

Had no idea what a Magnehelic gauge was before now.  Nice to learn something new 

I am tempted to get my Techstream software out now and see what mine is doing even though I don't have any white smoke.  When you say the pressure values were all over, what kind of readings were you getting?

Either way, I suspect you are going to be helping some members with this info, so thanks for the write up.

[steve2006]

Hello and welcome to the LOC.

What a fantastic first post, thank you for taking the time and effort in providing such a detailed report which may prove invaluble to other members with the same issues.

May I ask what trade you are in, I would presume automotive?

For those like me that have never heard of the test device here is a picture, still non the wiser in my case.

[Badger1966]

Hi smutts,

Awesome post. I have often suspected a wiring fault. And I wonder if I am suffering the same problem. Although mine is not smoking now. Could still be wiring some ware else. I am going to try the leak down test first and go from there. Congrats on your fix, which may well also help an awful lot of people! 

[lexy220d]

Hi guys! 

My one is a smoker as well but I just disconnected the 5th injector fuel line and I put the old 5th injector on so it wont leak and no more smoke but I got the lights on the dashboard now!

[rattler1968]

This is very interesting .... Mmm

[rattler1968]

hi this is a great post , i have a smoker.... i have been cleaning the erg , which stops the car smoking for 7-800 miles , but when i take the erg out, i take out the Battery!!!!.....which then resets the ECU!!!.... which is actually stopping the smoke!!!!  .... this week is was smoking like mad, after reading this post, i disconnected the Battery .... and 2 days later no smoke, i know it will return , but right now , its running great! so how do i go about changing the wiring? is it easy? shouldnt lexus change it??? ... had the car 2yrs not used any oil/water and runs like a dream except the smoke .......

once again great post!

[Badger1966]

Well my smoking was the Air Fuel sensor in the exhaust. And although you clean the EGR, is it actually working properly? Also Lexus wont "repair your wiring" They will charge you a fortune to replace the wiring loom with no guarantee of a fix. You will have to do the wiring thing yourself or find a competent auto electrician that can follow what "smutts" has done. It's all a bit trial and error with this car as different people seem to have different reasons for the smoking issue. Good luck!

[rattler1968]

3 hours ago, Badger1966 said:

Well my smoking was the Air Fuel sensor in the exhaust. And although you clean the EGR, is it actually working properly? Also Lexus wont "repair your wiring" They will charge you a fortune to replace the wiring loom with no guarantee of a fix. You will have to do the wiring thing yourself or find a competent auto electrician that can follow what "smutts" has done. It's all a bit trial and error with this car as different people seem to have different reasons for the smoking issue. Good luck!

Thanks for the comment, something to think about .... But a"smoking" is 220d is a problem and is something Lexus should be looking into? The car is working perfectly, apart from the smoke, and the smell of unburnt fuel, which can't really be passing emissions tests (VW?).Everytime I start up I think , "there goes a polar bear"   

I do like the car ...And to be far it does easily pass an MOT ? (2009 model ) only does the smoke on a run ..   Around town. In traffic when everyone can see!!  😱 

 The smoke is a nightmare 😫and dangerous if you are behind , following .... 

[Badger1966]

Lol, I know what you mean about the clouds of smoke. I sure wouldn't like to be the car following. But your car is out of warranty. And Lexus may be aware of the issue, but they ain't gonna do anything about it. This engine is something Lexus would rather forget. I have been there and got the t-shirt. Have you read my post? By the way, do you have any fault codes?...

[rattler1968]

18 hours ago, Badger1966 said:

Lol, I know what you mean about the clouds of smoke. I sure wouldn't like to be the car following. But your car is out of warranty. And Lexus may be aware of the issue, but they ain't gonna do anything about it. This engine is something Lexus would rather forget. I have been there and got the t-shirt. Have you read my post? By the way, do you have any fault codes?...

no i dont have any fault codes, had a garage wire it up, and they found nothing wrong with it? also sailed through an MOT ...? it smoked all that day. .Since disconnecting the Battery thursday? no smoke.........maybe i should just disconnect the Battery when it starts again? its easy to do .....?

[Badger1966]

No codes? Well it might be worth taking it to Lexus and getting them to do a "live" test. It took them an hour and a half to see that my air fuel sensor was intermittently cutting power to the MAF sensor. When this happened the engine note changed and a puff of smoke came out. Its an expensive item so may be best to get it diagnosed properly. Cost me around £300 fitted. And as with you, it only happens around town. Bristol Lexus are very familiar with my car so they may well be able to diagnose yours quicker now they know what to look for.

[rattler1968]

Mmm worth thinking about , thanks... 

I actually love the car , but this problem is a real pain in the arse .... I do mainly short journeys , don't think that helps,but I use dpf addictive cleaner , every 2000 miles ...  Not sure if they work but As of yet never had a warning light or error codes...  Mine has done 110 thousand .... 

I will look into your suggestion , but right now , with resetting the ECU .... No smoke?? For the time being ..... 

Not sure if there is a down side to disconnecting the Battery,  but it's an easy solution? 

[Badger1966]

Disconnecting the Battery just resets the ECU, and as you drive afterwards it then learns again so the fault comes back. Over time I suspect the fault will come back quicker and quicker though. But keep in touch and let us know how things are going.

[rattler1968]

On 02/05/2016 at 10:06 AM, Badger1966 said:

Disconnecting the battery just resets the ECU, and as you drive afterwards it then learns again so the fault comes back. Over time I suspect the fault will come back quicker and quicker though. But keep in touch and let us know how things are going.

Hi badger, just letting you know , it's 2 weeks , and the car has really cut down on the smoke, not completely, still gives an odd puff, which  doesn't last very long , and acceptable ... Ish... It's done about 400 miles, since disconnecting the Battery. It still has that smell? Though

Mpg is 31 mpg ... Slightly up ... 

Not actually fixed but less embarrassing driving around town . 

[toffee_pie]

if you mainly do short trips you are better off shot of it and buy a is250. Someone had to say it! You should probably consider selling it while it still in resonably -ish usable condition.

[rattler1968]

Ok 700+ and apart  from an odd puff , it's doing OK ? Before , I had clouds of smoke... really bad. 

All I did was disconnect the Battery??

Any comments? Negative would be good? Because I am confused? Surely can't be that easy? 

[smutts]

Sorry to have not been back, forgot the password & the reset didn't seem to work when I last tried to get in.

I'm an engineer, but not from an automotive back ground. As to cars, when younger, I just got fed up with paying experts and ending up walking to a phonebox in the middle of nowhere more often than I would like.

The biggest problem with this white smoke issue, is the engine computer doing bad guess work when it gets bad data from somewhere, (didn't computer programmers use the technical term GIGO? (garbage in = garbage out)).

The engine computer adjusts and evolves it's settings to what it is told by the various sensors. Unfortunately, if one of the sensors is telling fibs, the computer believes it, rather than saying that's moopoo and ignoring it. This causes the computer to do some weird things with the fith injector, AND IT DOESN'T THROW AN ERROR CODE! so often garages will be helpless as the computer doesn't tell them what to do.

If you own one these cars, you need techstream and the right cable, bootlegs from eBay are available, we were desperate so took the risk, and were ok. I'm always scared plugging one of these cables into a mostly working car, wondering if I'm about to brick the computer. Fortunately it worked.

If you look at the table on this link http://www.lexusownersclub.co.uk/forum/topic/74603-p2002-fault-code-is-220d/?page=2 (picture won't post for some reason) The bit that was interesting was my "dpf differential pressure", which was all over the place, and causing the fault due to knackered wiring, and the "exhaust fuel addition FB" which is the fith injector.

When the Battery is disconnected for five minutes & reconnected, the exhaust fuel addition value will start at it's default which is 1.0, ours when smoking had crept up to 1.45, presumably nearer to 1.0 is good.

How do you tell that the DPF is regenerating? When driving, and the pressure gauge and techstream agreed that the dpf pressure was over 5kPa (20 inches water gague) an orange ring lit up around the speedo. I assumed that this was to say the DPF was regenerating, it didn't happen at any set speed, but I can't find any other info about this. Was I wrong?

Thing that may cause the fuel addition to go up? These are my guesses.....................................................

Wrong DPF pressure data, due to sensor or wiring.

Out of spec lambda sensor? or buggered wiring?

Buggered temperature sensors for the dpf, or their wiring? "exhaust temperature B1S1" & B1S2

Who knows, but if it's smoking, see what your "exhaust fuel addition FB" value is.

Anyone buying one of these cars needs a good hard test drive, just in case the Battery was disconnected just before you turned up!

 

[Badger1966]

Hi, interesting theory. I have read somewhere else the same thing and it was a wiring fault from memory. I also posted pics from my techstream, they are on the first page of my post. See what you think. Although all readings were when the car was stationary but I guess it's also showing stored data from when I was driving. Would be interested to get your feedback. 

[hush33]

Hello guys,

I have the same problem as OP, white smoke & poor MPG

I tried to private message the OP but it seems he's not on the forum anymore.

I want to try to fix the wire but I dunno how to do it, anyone here can help ?

Thanks

 

[Shahpor]

Welcome,

If you are not sure, perhaps it is best left to a professional?

Ideally, like the OP, you would want to check it first via the TechStream software.

What makes you think it is the wiring?  Have you checked some of the other reasons it might be smoking?

[Badger1966]

Hi hush33 

My white smoke problem was put down to the "air fuel ratio sensor" in the exhaust. It intermittently cut power to the MAF and so it injected more fuel. Mine only did the smole thing in winter, or should I say below approx 8 degrees. I no longer have the car so I can't say for sure it fixed it. But it did fix it while on a live test at Lexus. Originally the cars engine tone changed and it also put out a puff of smoke, after the new sensor was fitted it no longer had the symptoms, do I assume a fix. 

It's not a cheap part, over £300 from memory fitted at Lexus, and of course the hour and a half live test to diagnose the problem. But I have to say, Lexus Bristol were awesome despite not being able to diagnose why my car had a P0093 fault. Although I fixed that myself, lol

[Iuliu andrei]

On 25/03/2016 at 2:11 PM, smutts said:

Just a potential FIX for you bashing your head against this particular wall,

The problem, a 2008 is220d, 110k miles, with embarrassing quantities of white smoke from exhaust that smells of diesel fuel.

My parents car has been smoking like a pig for the last few months,

Diagnosis....
Garage condemmed the DPF and replaced it..................Still smokes.
Garage says "just keep driving it, the smoke will soon stop"............It didn't
Garage says "er, drive it some more"...................Still smokes.
Garage yanks the injectors and send them off to be tested, by people who are not idiots..................non idiots send them back with the verdict, injectors are perfect...........................Still smokes.
Garage now say they are sure it is the turbo which will need replacing...................At which point I get involved and rescue the car.

No sign of misfire, compressions good, no play on the supposedly fragged turbo, no headgasket doom.

Not trusting the fifth injector, I unclipped the fuel line and plugged it by clipping another injector on it.

Went for a drive, white smoke gone! So confirming fifth injector misbehaviour.

Changed the fifth injector, a total git of a job............Smokes, Argh!

So it is the ECU telling the fifth injector to keep on squirting.

Techstream turns up from ebay, so plug it in.

The dpf pressure values are all over the shop, so tee in a magnehelic guage, which disagrees with the values from the software.

Wiggle wiring, AHA! Gotcha! Pressure values in the software change in sympathy.

So I remade the wiring from dpf sensor to the ECU and then got good values for the dpf sensor pressure.

The ECU "learns" whilst you drive, but the corrupt dpf pressure data had totally confused it. Unplug car battery for ten minutes, reconnect, ECU starts to relearn with good data. Relearn the window winders by driving them for a couple of seconds against their stops at each door switch.

AND THE SMOKE STOPPED! and mpg has gone up from 25mpg imp to 40+mpg imp.

The magnehelic gauge reads 5kPa (20 inches water gauge) when regeneration of the DPF now starts.

So to recap, check the DPF pressure sensor to ECU wiring carefully before spending lots of money on the garage partswap goosechase.


Good luck on what is a fantastic car.

Warning!!!!!!!!!!!!

! I only disconnected the fith injector for long enough for diagnosis, if it is disabled for too long, the DPF will probably clog up! I only disconnected it for 20 miles.

Can I leave the 5th injector in and disconnect the power supply? My injector is new and the Dpf  as well 

[hush33]

Hello guys,

Winter is coming and....

....the smoke is now unbelievable... its now more like a cloud behind me... my mpg is decreasing aswell...

I know its better to let a professional do the fix, but when I contacted LEXUS BORDEAUX (FRANCE) the mecanician dont know about this eventually wiring fault...

 

 

[Badger1966]

Try getting Lexus to put it on a live test and see if the air fuel ratio sensor is faulty, or intermittently faulty. It was causing problems on mine and was cutting power to the MAF sensor. This was causing it to overfuel and smoke.