Rough idle & clicking rear offside wheelarch.

that would be the FBH, i supose the ticking is its pump, maybe on a really cold morning when the FBH is operating, you could disconnect it and hear if the clicking stops, then you know the clicking is related to the FBH, it happens to mine in the cold mornings but havnt investigated yet.
I really dont know what use the FBH is as the cabin doesnt get warm quicker than it normally would without one, waste of fuel if you ask me.

Hello again NavyReg,

What you are describing is the correct operation of the fbh (fuel burning heater)

At low temperatures (approx 5 degrees C) it will start up automatically to reduce the warm up period. It will switch off automatically once the thermostat opens.

It is in the front near-side below the headlight unit in the engine bay it burns diesel and has a little exhaust for the white smoke it produces below the n-side front bumper. It makes a 'whooshing'sort of sound.

It has its own little pump beside the wheel-arch pump and filter. It burns only 250ml per hour.

Without it your TD4 which has a huge radiator and has approx 8.5 litres of coolant would be very slow to warm up.

You can get a timer to make it operate just like a cabin heater in an HGV sleeper cab - I have one it's great, but pricey.

cuts out once the thermostat opens? interesting

i attempted to change the stat on mine a few months back but couldnt do it, as my cabin wasnt getting warm (thinking it could be lazy stat), but since this really cold weather is kicking in, its getting warmer but only through the windscreen demister and footwells, no hot air atall through the main vents.

garrytd4 said:

cuts out once the thermostat opens? interesting

i attempted to change the stat on mine a few months back but couldnt do it, as my cabin wasnt getting warm (thinking it could be lazy stat), but since this really cold weather is kicking in, its getting warmer but only through the windscreen demister and footwells, no hot air atall through the main vents.

Click to expand...

Yup, that's how mine behaves anyway. It has it's own temp sensor somewhere behind the front bumper to sense when to switch on and it seems to switch off before the temp gauge gets halfway to normal.

As to poor heating at footwell -
Check pollen filter housing is clear - take out pollen filter and feel up inside (I used a small paint brush handle to dislodge chestnut tree leaves)

Also try bleeding the cooling system just after start up from cold with the heater temp control set to max.

sorry, im getting warm air through footwells, cold air through main vents, pollen filter is removed. system bled, the temp gauge takes all day just to get to halfway, i can drive 30 miles on the motorway and the gauge will still read cold.

sorry for changing the subject on this thread