paul.h

What model/year car is it, how many miles, when were brakes last serviced (miles/date). Maybe the brakes need a clean to remove brake dust which is causing the pads to stick or pistons are seized or pads are worn out or maybe a brake fluid leak - is the fluid level ok ? I would have a good look over the entire system with each wheel removed and make sure all is ok checking for wear and leaks and faults with the brake hoses such as bulges. If possible have a helper to push the brake pedal whilst you check each brake hose and each wheel is free to turn and then stops when the pedal is pushed. Remember to set the suspension to max height before jacking up unless you have the mark 3 C5 without hydraulic suspension.

Welcome to the forum. What were the symptoms and were the brake discs wet from rain ?

Check the battery to see if fully charged. I think there was a post recently with odd electrical problems and I think it was due to the towbar electrics getting water in the 12n/s sockets but not sure - worth checking they are clean and no earth faults though.

There may be a menu button on the radio to change settings as on our C4. If there is a button on the end of the wiper stalk that may change values. With the engine running, push in/hold in the inside door locking button until the auto lock is switched off.

Knocking on our car was from worn anti roll bar drop links, difficult to tell even when removed from the car but once replaced the noise had gone. The MOT tester had advised wear in one of them.

5.6 litres is the value in Haynes. Citroen use a type of anti freeze that does not normally need replacing so if you are not using the same stuff I would give it a good flush to remove traces of the old before using the new and then do replacements as required for the new type eg every 2 years.

Should find the number on the DVLA registration documents, the car service book, on the car in the lower left corner of the windscreen.

I did a post on replacing this a few months ago, should find with a search. You will need a long thin torx screwdriver before starting the job and at least one spare set of the 3 screws to replace the ones you will lose or even damage. If a dealer will do it for 30 mins cost it may be worth letting them. If you start the engine you will see the rod has moved from the engine not running position which shows the electronic valve is working. Oddly just before I found mine needed replacing, I had just been getting around 60 mpg on a couple of M62 trips from home to Hull (110 miles each way, total 440) but these were slow due to roadworks, the weather was good, no wind, and I had put some Shell expensive diesel in. Now back to about 50 mpg for the same trips but roadworks gone, Sainsburys fuel and weather not so good. Do not know when the diaphragm socket broke and there were no symptoms.

There do not seem to be many posts yet on the new C5 but there is now a French Revue Technique Automobile manual available for the 1.6 and 2.0 hdi cars from 2008. Amazon do not have it in but can be obtained from the ETAI.fr site which redirects to passion-automobile. The website is in English (select flag at top right). If it is as good as the ones for the older C5s it is worth having especially since Haynes will be years away before they do one.

If you look through or behind the rear wheels you will be able to see if there are brake discs (= pads) or drums (= shoes). Probably around £200 for a garage to do but ring one up for a price.

If you push the button on the end of the wiper stalk you can change from instantaneous mpg to average mpg and the value will not change as frequently, further pushes give distance since last zero, distance to fuel tank empty but this varies with current mpg being achieved. Push and hold the button in will zero the values.

The metal plates on the back of the pads are anti squeal shims. When new they are often bonded to the back of the pads but as they age they can come unstuck. If there is nothing else to hold it in position (such as the caliper design on the C5 rear brakes) then these can (should ?) be removed but you may get some brake noise. If you think the pads are binding (see if each wheel spins freely), I would remove them and clean off all the muck.

Not had this problem but I use a torque wrench when doing the bolts up and also after they have been done up by others since they are often overtightened. It is worth making sure the bolt threads are clean and with a slight smear of copper type grease. If you have alloys, also have a slight smear of copper type grease where the wheel contacts the hub so they do not rust on. Your old bolt may have been drilled out.

My dealer contacted Citroen without even me asking to see if they would pay for the work and was given the go ahead - if not I would have paid anyway (we did not have a warranty at that time). We have bought 4 cars from them and have them serviced there also so this may have helped and we have no problems in going back there. I would recommend them to anyone - Barclays, Warrington.

Something like silicon sealant sticks/seals most things, just needs to be water resistant.

I think diesels only had to comply from 2004 but I would have a look on the Gendan website and maybe contact the sellers. I got a Sealey PSA one from them but when reading live data it does this as OBDII so could be read by any reader.

Replacing the front anti roll bar drop links stopped a knocking noise on our car - this was picked up at a MOT as wear in one of them. I also found in the boot there is a loose plastic side to a cubby hole which I packed out with card on the driver's side.

If a petrol we get 45 mpg most of the time. One bar on the fuel gauge is about 1½ gallons so will give you an idea between refilling.

Best thing to read the temp is using a code reader which gives live data and then see if the values are realistic. This though could cost more than a sensor.

Next thing could be a temperature sensor fault thinking of something else (which also is lowish cost) that can affect fueling. Does it use any engine oil ? Is the air filter clean ?

I think our C3 was about 5 years old when the springs were replaced without cost to ourselves and any warranties had long expired.

Possibilities without removing the lamp could include - With the back cover removed it may dry out with the headlights on. Using a hairdryer on cold may also help by blowing in air to remove the warmed but damp air. As a pipe you could borrow something from a vac to direct the air at the lamp opening if your hairdryer can not get near enough. Park the car on a dry sunny day pointing at the sun with the back cover removed. If you have a garage, park the car inside overnight or longer with the back cover removed. Rather than buying a new lamp/cover, why not just clean up the existing seal and apply a bit of sealant when fitting the cover again or it may just be the cover was not put back properly in the first place since it is a bit awkward and I have seen similar comments here before.

Has it just started recently with the cold frosty mornings ? If so it could be a glow plug problem.

I take it the cabin fan is not working. Possibilities could include a fuse has failed, a wiring problem, the fan speed control resistor pack may have failed, the fan motor may have burnt out, a problem with the control system.

It will tell you in the service book if needed. On the mark 1 hdi it is at 37½ to 40k miles. The filter may be about £18 and 10 mins to fit.