Re-mapped Mk2 Leon 1.9 tdi smoking lots when accelerating

[KWJones11]

Hi there

I have a 2007 Leon 1.9tdi. I have had it re-mapped and an extra 30 bhp has been added.

It has been approx 2 months since I have had this done.
The Mpg is pretty much exactly the same and returns 60mpg at best, and averages around 50 mpg so I am very happy with this.

Only problem is, when I do put my foot to accelerate then I leave a trail of smoke!!!
The guy who re-mapped said its just clearing out the system when it was first done. 2 months down the line and its still doing it!

Any ideas? Anything I can do to remedy this?

 

[vroomtshh]

He's upped the fuelling on the map, so the car is using more fuel than it needs to.

Not really any way of fixing it, except having it mapped again

 

[gregdaisley]

What brand of map did you get?

 

[KWJones11]

Okay thanks for the info. I was hoping I could buy something to put in the diesel to clean it / reduce it possibly. If there is nothing that can be done then so be it. Thanks for the response, much appreciated.

I am not sure what the brand was. I had it done with a guy who is mobile that knows a friend.
The performance wise is quite significant which I am very happy with no effect on the fuel consumption.
He just informed me that its approx an extra 30 bhp, preformance/economy based?

 

[gregdaisley]

You could try Miller Oils - Power Ecomax fuel additive, its what I use and gets a good write-up.

To be honest with you, diesels will smoke at higher rev's as they NEED to over-fuel slightly to continue accelerating.

My 1.9TDI has a REVO map on it, rolling roaded @ 141bhp and it does smoke if I floor it, but not excessively.

 

[Muttley]

You realise you've opened a big can of worms here, don't you?

Remapping improves engine output by pushing the leading parameters towards the edge of the performance envelope.

The standard map will have been written to allow an engine that has all its components at the low end of their tolerance to still deliver the rated performance. Most engines are built with components that meet the specification, and can deliver extra output. This is delivered by increasing the boost pressure (to get more air into the combustion chamber) and increasing the injected fuel quantity (to make use of the extra air). A good map will match fuel and air quantities accurately and avoid smoke production.

Smoke is part-burned fuel - the hydrocarbons in the fuel have not been completely oxidised to carbon dioxide and water, and some carbon is left behind, suspended as fine particles.

The principal cause of smoke on heavy acceleration in all modern diesel cars (not just remapped ones) is the EGR system. This work of the devil is supposed to control emissions of NOx, nitrogen oxides, by reducing the combustion chamber temperatures at times of sudden peak power demand. High combustion temperatures form NOx - it's got hot enough to burn nitrogen.

However it is well known that EGR in diesels produces smoke. The principal that EGR works by is to introduce inert gas into the inlet charge, so of course there's too much fuel all of a sudden. Even the standard map can be induced to smoke a little if you put the boot in. This is one reason why DPF's have become mandated by pollution-control minded legislatures.

I'd try getting your EGR system turned down to minimum, which can be done with VCDS.

 

[gregdaisley]

^^ Great bit of info there Muttley!

Regarding the EGR setting on VCDS, where is that found? Within the Engine Control Module I assume? Oh and setting it to minimum, what needs to change?

 

[Muttley]

I can't tell you straight away because my VCDS hasn't arrived yet. However it's been posted on the forum a few times - a search should find it - I found the thread below straight away

http://www.seatcupra.net/forums/showthread.php?t=287688

 

[gregdaisley]

Thanks buddy! I'll give it a go tomorrow night when I'm back down south and let you know how it goes!

 

[john_tdi]

Good advice re the egr. A good clean out will help. However if it was still the same after, I'd go back to the mapper, and say your not 100% happy.

 

[gregdaisley]

@Muttley

I was out at the car this morning and couldn't seem to get that EGR adjustment to program

This was my post in that particular thread...

Can anyone give me some much needed advice...

I'm out at the car just not attempting this on my 1.9TDI 105bhp Leon Mk2, it has a Revo remap so it can be rather smokey at times and apparently this will reduce the plume?!

The problem I have is when I open up my VCDS 10.6.0 and enter the engine module, the Login - 11 tab changes after a few seconds to Coding ll - 11. I have clicked this and tried to enter the 12233 code but it will not accept it?

What do I do next?

Many thanks, Greg.

 

[majesty78]

EGR system only works at part throttle.
Smoke @wot = bad remap