Smoke on cold start up TD4

Spoke to a really experienced mechanic used to working with TDi's ..... he recons mine is due to slightly worn Turbo seals ...... he recon's it's nothing to worry about - unless the car starts to run on. Undo one of the intake hoses from intercooler (the one that goes over engine) and run your finger along inside bottom .... after the car has been left standing overnight ....... I bet you have a liberal coating of oil ..... mine has. Mechanic recond it could run for a couple of years before giving real trouble. This guy rebuilds turbos and recons Garret do a kit to recon this turbo ...... costs about £150 quid .... that does not include removing turbo!!! I know my car has suspect service history between 65k and 105k .... I suspect infrequent oil changes and inappropriate engine switch off has taken it's toll on mine..... I will leave mine unit she starts to run on...ulp.

Hi all have changed diesel filter but am going to remove injectors again and deburr ports and use some more sealing washers rebuild it and try again so after weekend will report again to you all.

There is always oil in the inlet hoses on tdi's, if you check the inlet to the turbo you'll find it comes from the crankcase breather discharge.

Well removed injectors beburred ports spent 9 hours on it changed MAF sensors and still the same what a wasted day i am now p........d off with it has anyone any ideas am wonderin if ecu is faulty or is there any temp sensors need changing that links to ecu to cause it to overfuel hence blue smoke because when it gets hot blue smoke disapears HELP.

Phil0114 said:

Well removed injectors beburred ports spent 9 hours on it changed MAF sensors and still the same what a wasted day i am now p........d off with it has anyone any ideas am wonderin if ecu is faulty or is there any temp sensors need changing that links to ecu to cause it to overfuel hence blue smoke because when it gets hot blue smoke disapears HELP.

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oh man..feel for ya mate gotta be looking at turbo seals or valve stem seals me thinks??

Hi Marky thats what I was told turbo seals........... inlet seals weeping causing small amount of oil ingress. Removing Turbo is a mother of a job ...... It looks like it is a toss up between Turbo and Injectors ...... or both dohh

D3savage said:

Hi Marky thats what I was told turbo seals........... inlet seals weeping causing small amount of oil ingress. Removing Turbo is a mother of a job ...... It looks like it is a toss up between Turbo and Injectors ...... or both dohh

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hmmm.....well my thoughts are....if it was turbo seals it would just belch out a bit of smoke but not affect the initial start-up lumpy tickover which is why i am more drawn to either injector or valve stem seals and i've got to say my very first thought was the valve stem seals and having changed everything but those i'm beginning to think my guts were right.....:doh:

Hi markyzs1800 we have changed all 4 injectors changed glow plugs and maf sensor and crank ventilation filter but it keeps belching blue smoke out its worse when i fitted egr removal kit so now it has got egr valve back in when it gets to operating temp the smoke disapears and it drives perfect stop it for five mins when it cools down abit start it back up and blue smoke returns its a total mystery

hi chaps here is an update have spoken to a chap who is a bosch diagnostic specialist and he said the timing chain on these stretch causing the timing to alter (as they should fire at 6 degrees BTDC) so it starts fueling early causing extra fumes through pumping in extra fuel so what we have done is had a map made for the car so it fuels at 8 degrees BTDC with a little extra power and increased MPG The Good News Is that it goes like a train and the smoke problem has got a lot better obviously its never going to dissapear totally but its a million times better and the uneaven idle has almost gone will keep you all informed as week progresses to see if its still ok.

Have to disagree with your 'specialist', a streched chain can't cause injection timing to alter since it's ecm controlled.

Hi Phil sounds very interesting..... mine bleches out blue smoke on cold starts exactly like yours did ...... please keep reporting back. Also for me please can you check to see if you have oil in the air ducting hoses from intercooler...... I am convinced this has something to do with it...........oh and could you put your EGR bypass back in....and monitor.... Cheers

Will do no probs

Chaser said:

Have to disagree with your 'specialist', a streched chain can't cause injection timing to alter since it's ecm controlled.

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Hi yes i no that the timing is ecu controlled but when chain is stretched it causes extra travel in chain so when the crank and cam sensor tells ecu to fuel then with the extra travel in the chain it may only really be at 4 BTDC so advancing the timing theoretically by telling ecu to fuel at 8 bTDC by a remap it is only fueling at 6 BTDC as if it had a new chain hence no extra fuel and less smoke being produced.

This problem seems to roll on and on - I'm feeling for you - I know how worried / puzzled you must be.

A few things come to mind.

The EGR can make no difference to the smoke at all - whether it has been by-passed or not.

As Chaser pointed out, there will always be some oil in the turbo pipes - esp. at the 90 degree bend one - the turbo turns at a ridiculous number of revs and as far as I know the shaft 'floats on oil' so there is always 'blow-by' to some extent.

As far as I was aware there is only one make of turbo fitted to the TD4, and is the Mitsubishi MR1 TD025L3 not the Garret - perhaps I'm wrong.

Keep at it guys - you'll get there yet. I just hope it isn't valve stem wear.

Phil how is the smoke situation has it died right down....after time with the remap???

D3savage said:

Phil how is the smoke situation has it died right down....after time with the remap???

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Hi there is no where near as much being kicked out on start up originaly it puthered out now there is alittle on start up then next to nothing now we need to refit egr conversion kit and monitor it to see if its sorted i will keep you all informed step by step and if its all good maybe everyone will be happier thanks guys

Phil0114 said:

Hi yes i no that the timing is ecu controlled but when chain is stretched it causes extra travel in chain so when the crank and cam sensor tells ecu to fuel then with the extra travel in the chain it may only really be at 4 BTDC so advancing the timing theoretically by telling ecu to fuel at 8 bTDC by a remap it is only fueling at 6 BTDC as if it had a new chain hence no extra fuel and less smoke being produced.

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Sorry fella but this is total crap. If it's your mistake then fair enough but if this has come from your specialist then he ain't that special and you should stay well clear.

Hi Chaser.....are you saying ... that as ECM controls injectors....which injects via instructed signal..... then there is no connection??? What about the cam sensor.....if the chain stretches then the ECM is getting the wrong cam timing.... so could it be a case of crap information in crap information out .... hence slightly wrong injection timing???? Is there a crankshaft position sensor on these cars monitored off flywheel???
If this were the case then chain stretch would be irrelivant. I suspect on the TD4 due to dual mas flywheel .... cam wheel position is sensed.....therefore this would be subject to chain stretch effect - there is a helava lot of chain between top and bottom of engine. I am still open to the argument .....Phil just keep us all posted ... this is an interesting thread.

Of the two the ecm uses the crank sensor signal only for injection timing purposes. The cam sensor role is purely to establish when #1 cylinder is on its compression stroke during start up and plays no further part in engine running.

In any case if it is believed that camshaft timing/position is incorrect for any reason then that can and should be corrected mechanically.

Hmm logically then cam chain stretch has now impact on timing ..... oh well I am stumped....