I have a Peugeot 406 2.1 diesel which usually when warm has a revving issue. When its ticks over the engine hunts from 1400 rpm to 1600 rpm and when I change gear it almost revs into the red line when I put my foot on the clutch. I have had it plugged in for diagnostic and it said engine coolant temp fault so replaced the sensor but has not made any difference

Engine Number
Can be found on the nearside centre of the block half way down, but may vary with engine model.

have heating in my peugeot 406 hdi when car is ticking over but when i drive for few mins the heater goes cold

Its a dpf not a cat.Easy way to clean out[regenerate]First bring the engine to normal temp bring up the rpm to 4000 for 2 mins,then allow to idle for 30 seconds then bring the rpm up to 3000 rpm for 3 mins and yourfilter will have regenerated [fancy word for clean itself out. DPF = diesel particulate filter.Its important to use good quality low ash oil for your oil changes.

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

switch has broke inside itself

it will be your low volume pump in the tank

May be it can help you.
http://www.gigasize.com/get.php?d=yzwy0qgn85b

idle air control valve

have you changed a peugeot or citreon 1.9 or1.9 td, if so its the same.

very hard to diagnose these cars go to dealer and get checked it is the only way to fix these kind of issues