I ran my peugeot 406 out of diesel and i think there is an air lock as it starts but doesnt keep running? i had to click on 2006 peugeot 405 as it wouldnt let me select a product. my car is infact a 1996 406

406 1996 Diesel would either be 1.9D, 1.9TD or 2.1TD

Each of these use a vacuum type distribution pump, which means once the fuel has managed to get to the pump via means of initial priming it looks after itself by constantly sucking fuel. If the engine stops after a a short time it could be a blockage caused by running very low on fuel. First thing to check is the primer system. You may have the squeazy balloon type or the purflux set up with a hand primer button. The issue is common to be at this point but hard to diagnose.

What I have done in the past is disconnect the pipe going to the main pump and given a seperate feed from a pipe submerged in a can of diesel, if it runs fine then it rules out mechanical and pump issues leaving it only to be a supply issue.

Regards

Lloyd