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Billy, Trainer/Master tech.
Category: UK Car
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Experience:  Trainer - master tech., SAE member
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A3: Ive just brought a 2007 a3 170bhp its had the dpf removed

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I've just brought a 2007 a3 170bhp its had the dpf removed and been remapped not by me thou the problem I've got is when I start the car it's starts smoking until its hot then stops smoking it smokes a lot beforehand and smells of a strong burning smell I've had the car over a week it's done 78k and passed mot yesday no problem couple people said this is normal when its had dpf removed and remapped ?? Is this true or have I got more of a problem ??

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Customer: replied 4 years ago.
I don't mind waiting a little longer il try give you more information when I first start the car it's sound rough for a couple of seconds and starts splutering if you no what I mean for about 4 minutes then it stokes to smoke white gray smell till the car is at full temperature then smoke goes and doesn't come back till the car as stud for half hour Or cooled down abit then smoke quite heavy until warm again but the burning smell stays there all the time car seems to run fine when going checked oil couple of times and doesn't seem to of lost any but not a 100% on that hope this helps you more
Cheers Malcolm
Thank you for your continued patience. We will continue the search for a professional for you.
Hello and Welcome!
I'm Billy and i will assist you with your inquiry.
Feel free to ask if any further info is needed.

My apologies for the delay, thank you for your patience.

Is is smoking diesel (black soot) or oil (white bluish) or plain water vapor?
do you have any other problems or symptoms, or even have the check engine light on, or other warning lights?
Customer: replied 4 years ago.
It is burning diesel smell all the time and the smoke is white and grey there is black smoke when u rev it up when its smoking but clears up with in seconds then smokes again when idling all this is when car is not at full temperature when it is at full temperature it smokes very little light grey but the burning smell is always there !! I've done some research well waiting for you to get back to me and a couple of people with smiler symptoms who had the dpf removed and remapped said it was the mapping that was set up wrong had the remapped deleted and reinstalled and the car was fine does this sound like the case with mine ??

If you have a burning diesel smell, and the smoke is white to grey, then it is diesel.

This means that you have excess diesel being injected to the engine. So if you have no other symptoms, and no other problems, it means that the ECU (engine control unit) is ordering the excess fuel when cold (more than enough), so it would be caused by the programming (the mapping). So upgrading or installing the program again (remapping) should cure this.
This certainly looks like the case you are having.

Thank you for your trust! Get back to me if you need more info...Thank you in advance for the positive rating...

Regards, Billy
Billy, Trainer/Master tech.
Category: UK Car
Satisfied Customers: 3498
Experience: Trainer - master tech., SAE member
Billy and other UK Car Specialists are ready to help you
Customer: replied 4 years ago.
Hello again
Just let you no I've had the remap done today and the runs a bit beta but still got this smoke the guy said that is normal as there is no dpf catching all the smoke and cleaning it could this be right ??

The DPF stores most of the particles. But even without it you should not get excessive smoke out the exhaust. So you would get some smoke (particles) but just like the usual diesel.
Customer: replied 4 years ago.
It's a lot of smoke starts after the car as been running for about 3 minutes from cold but when driving it goes and when its on full temp and you stop it doesn't do it just get a very little bit of smoke have you got any idea what could be coursing this please as I'm running out of ideas

So when the engine is cold you get smoke with a diesel smell, and when the engine reaches operating temperature the smoke goes away.
Do you have any warning lights on?
do you have any other symptoms (hard to start, reduced performance, hesitation etc..)?
is the vehicle serviced (fuel filter, air filter, and clean EGR)?
Customer: replied 4 years ago.
The place I've had the remap done said there is no codes showing it runs fine no smoke at all when driving just on first start up and when its below full temp no warning lights on at all oil level fine water coolent fine :-(
Customer: replied 4 years ago.
Got full service history last one done last year
Customer: replied 4 years ago.
The car doesn't seem quick for 190bhp its a bit rough when you first start and a couple of times it seems like its delayed then shot of again just been take it for a good run got it up to 90mph for about 10-15 miles each way seems fine at top end but got it back let it sit abit then started it up still warm started smoking again and then a strong smell of burning what I'm guessing is fuel when driving slow smell it coming few the air vents really worried now just wish I had a some sort of idea to what it is really getting me down spent a lot of money

So we are sure that the smoke is only present when excess diesel is being injected.
You should check the EGR make sure it is clean. AS if stuck closed it would cause symptoms like this.
You have no codes showing, i would suppose that you have no warning lights on dash.

Check these, and get back to me with your findings....

Regards, Billy
Customer: replied 4 years ago.
How do I check the egr ?

You need to remove the piece number 5 (EGR motor) which is connected to the valve. REmove the valve and clean it (as it would have soot or particles on it, clogging it or restricting its movement).