MEGANE HABLACLE SMOKE 1.9 TDI 95 hp

Please, help: I ​​have a smoke problem in my megane 1.9 TDI (95 hp) year 1997. The fumes occur when retaining, when a very long port is lowered you have to open the windows because you end up even with headache, the strange thing is that it does not do so when you climb or flat, only when retaining.
Covering the escape, no losses are noticed, looking at the escape unions either.
I think that the fumes can put them in the admission, but it seems very rare, someone knows if for a failure in advance of ignition, or for having badly made the distribution (some advanced or delayed tooth in the admission cams) can get to throw smoke by the admission when retaining and on the other hand, as I can check if it is where the smoke throws since there is no way to look in the cap while it retains.

A second consultation, the car also has an air intake in the gas-oil circuit, I have changed the circuit but I do not give it, maybe I could be inside the tank. Keep taking air when he wants and when it happens to him, he accelerates and loses power. Someone has had any such failure and can tell me where they usually take air when that failure occurs. Thank you so much!.

It is extremely strange friend, but I do not think it is a problem of tuning, although they can return gases to the admission it does not join the one that enters the vehicle, look if your escape has flexible perhaps this component is giving you the can.

Kikemec, thank you very much for answering. Indeed my escape has flexible between the turbo and the catalyst, but there I see no remains of smoke or appreciate anything weird. How can I check if it is from that part of the escape?

One thing is that it has a different remains than this good hahaha, look for what you say and describe in the failure, what happens is that the carbon monoxide enters the cabin, this is dangerous because on a long trip you can fall asleep behind the wheel, this component if it is the culprit, it can be broken somewhere I support the escape and move it if somewhere opens and releases gases anyway recently to a colleague happened something similar I will ask how he solved it just down the mine, and I write to you what happened. But trying by moving the flexible in all directions to be able to discard it completely, you only in one position throw gases.

Kikemec friend, I have disassembled the flexor and effectively the failure was there. As it goes at the top of the tube, it is seen inside the naked eye that is broken, you don't have to put smoke or do anything weird. I attach some photos. Not seeing anything externally believed that it was fine, but thanks to your contribution I di with the failure. Thanks a lot.