Unstable idle

Hello good, I have a problem and I need a little help. My father has a Renault 19 is a 19Diesel, the problem is the next one that fails and throws some white smoke and when we give the primer it stabilizes and does not fail while we brow it. How much you accelerate a little does not fail only failure in Ralenti. that's all. Please answer me thanks

You must have an air entrance to the diesel.
Heeted air bubbles and heads, steps on or ceres and throws the air.

Rebisate that you do not have diesel leaks, broken sleeves or the sleeves of the injectors are well.
The joints with the diesel filter, etc ...

that engine I think it is a rotatiba pump the same way you have some retain from inside and it takes air.

Dode see Gasoil's leak there is taking air and that makes you fail you.

The white smoke: Or it burns oil, aaahhyyy has a benido an inspiration, what happens that you will have the injectors badly and when it is in relief and do not spray as they should and when you achuchas they polber you and it is fixed from there is the smoke.

Take them out and start, if they do not pulverize and gotean they are dirty.

Thanks Igryo, I look at you, I thank you for your answer thanks