paul.h

What year is the car ? Was the noise there at the last MOT since wear in the suspension parts would be checked ? It is always possible the knocking noise is the drop link on the driver's side but just seems to come from the passenger side. It could also be the suspension strut top bearing. You could also check the coil springs all round are not broken/missing a bit. Maybe the shaking and rumble sound is the front wheels need balancing and possibly a tyre is badly/unevenly worn. The change since replacing the ball joint could be the wheel was not put back in the same position on the hub (90 or 180° round). It could also be a worn wheel bearing or maybe a worn CV joint, inner or outer.

May be when coastline taxis is back on the site he will have a few ideas. How many miles has the car done now ?

If it is not the connector then you may need a diagnostic check to see what is wrong, otherwise you could replace lots of bits before finding the actual fault.

I think the 2.2 hdi 173 bhp engine was only made for a few years, approx 2006 to 2009 and can be found on the mark 2 and mark 3 C5. As far as I know they have the twin turbo but for a specific car you would be best to use the car VIN in the parts diagrams.

In the turbo picture at the bottom and a bit to the left you can see the turbo actuator and from this there is a small diameter pipe which if you follow it a bit to the right will go the the solenoid valve.

That is a good result and about time you had a bit of luck. If you want you can give the details of the auto electrician on here in case others need any work doing.

On a C8 recently BigBruv had to remove a drive shaft from the gearbox but could not undo it at the hub end but managed by your original suggestion, so it is something you could still try. It also saved him from having to get a high setting torque wrench to do up the hub nut. http://www.citroen-owners-club.co.uk/citroen/topic/23870-now-my-turbo-has-blown/?hl=driveshaft&do=findComment&comment=89453

If you want a complete rear harness there are different ones depending on your car VIN. To get the part number you will need to look in the Citroen parts diagrams using your VIN and then look under Electric Unit, Electrical Harnesses, Rear Harnesses, Flap Harness/Rear Hinged Door/Chest - Saloon 5 door. In one of the above posts there is a link with others to how others have repaired the harness http://c4owners.org/print.php?plugin:forum.41895 and some have also moved the rear washer pipe to the other side of the door so the wires are not a tight fit in the rubber tube.

You could try these but I have never used them so it is not a recomendation http://stores.ebay.co.uk/LCS-Louth/CITROEN-CAR-SPARES-/_i.html?_fsub=1521382017&_sid=798770047&_trksid=p4634.c0.m322

Most likely the wires in the rubber tube between the tailgate and body will be broken and to fix it needs them joining together or possibly a new bit putting in. The full wiring harness would not need replacing. If you can not do this yourself then try an auto electrician and it should be nothing like the price Citroen have quoted.

Rather than rely on a dealer check, you could find a flat area with a brick wall at the end and shine the lights on it. The flat part of the dipped beam should be lower than the height at the lights. You could adjust them up a bit as long as they still point down. The check should be done with the car empty and with the light height adjuster switch on the dash (if there is one) set at 0. On the headlight will be a % value that is used to set the beam height and in the MOT testers manual it gives the tolerances for this. Some info here https://mattersoftesting.blog.gov.uk/the-mot-headlamp-aim-test-is-changing/

Citroen must use this type of cover for a reason, it has been the same on 3 C4s we've had 2008, 2011 and 2015, all 1.6 hdi. Yet other Citroens have had hard plastic ones so cost may not be the reason. May be it absorbs the noise better.

If you have a volt meter you could check the battery voltage but it would not be as good a test as a load test. Before starting the engine the battery voltage should be about 12.5 volts and once the engine is running it should be about 14.4 volts. If much less than 12.3 volts the battery needs charging or possibly replacing and may not have enough power to start the engine. On the C4 there is a positive battery terminal under a flap just in front of the battery and there is an earth point to the right of the radiator (when looking from the front of the car) which can be used if the car needs to be jump started. So with a volt meter set at about 20 volts, touch the meter red lead on the positive terminal and the black lead on the earth point to check the voltage of the battery. If you do not have a volt meter they can be bought for about £10 from places like Toolstation such as this one but there are similar looking ones from elsewhere and usually yellow in colour http://www.toolstation.com/shop/Electrical/d190/Electrical+Test+Equipment/sd3348/Digital+Multi+Meter/p11867 If you have a meter it can be used to help check the boot problem by checking for a 12 volt supply to the switch and if the earth from the switch is ok. You can also check if the switch works by seeing if there is no resistance across the switch electric connection pins when the switch is used.

Unplug the wires from the switch, then use a bit of wire in the plug to join the 2 electric contacts together.

That pipe connection must have been modified on later cars, it is different in this picture from our 2004 mark 1 C5 2.2 hdi and looks as if the pipe connects to the vacuum pump via a connector. This could be related to your turbo boost problems.

Before replacing the switch you can test if it is faulty by using a wire or paper clip to connect the switch wiring electrical connecter pins - if the switch is the problem then the boot will unlock, if not then the problem is elsewhere.

'The issue seems to be that an engine plug has come out whilst I was driving it.' Is this a core plug - I have replaced some on possibly a Maxi engine where they had rusted and one developed a rust hole but it may have been about 10 years old and had rusted from the outside. Was easy enough to replace, just put a bit of sealant on it and tapped the new one in to the hole. It was found quite soon after leaking though so there was no engine damage.

This topic starts as a C5 one but then becomes a C4 one which is worth a look http://www.citroen-owners-club.co.uk/citroen/topic/23731-2007-c5-estate-tailgate-door-will-not-open/ For the C4 it was the wiring and the switch. All the switch does is connect the 2 wires to it together so that the supply wire is connected to earth - so if you still have the switch off you could connect the 2 pins together in the electrical socket to it with a bit of wire or a paper clip to simulate the switch. Then if the lock opens you know the switch is faulty, if not then it may be the wiring or a fuse or possibly the lock motor.

Welcome to the forum

A common problem on the C4 is the wires between the body and tailgate can break in the rubber tube top left as you look with the door open. You may also find the rear wiper and any lights on the tailgate may not be working.

According to the Haynes manual for centre console removal, page 11.24: after removing the gear and handbrake shrouds, remove the plastic trim in front of the handbrake lever, lift the rear ashtray out and undo the 2 bolts now seen and then remove the rear section of the console. Then undo 2 nuts (picture shows 2 torx bolts) at the rear, slide the console rearwards a little and then lift the rear, manoeuvring it over the handbrake and gear levers. Some wiring plugs will need undoing.

As well as the new bolts, I would carefully inspect the towbar since you do not know how it has been used/abused. If in any doubt on any of the welds then you may be better getting a new one. Also remember to tell your insurance company you have a towbar since they will class it as a modification. It should not cost any more but if you were to make a claim and they had not been informed they may not pay out. Note that the bolts and nuts will be high tensile ones, possibly 8.8 or higher so may not be widely available.

Probably best to continue this topic on an existing one http://www.citroen-owners-club.co.uk/citroen/topic/23976-c5-suspension-fault-pump-maxi-fuse-blowing-fault-code-p1351/ where the pump motor has been cleaned to fix this problem so I will lock this one and all replies can be in one place.

Citroen's procedures for the C5 (X7) do not mention having to depressurise the suspension to remove the pump. 2. RemovingPut the vehicle on a hoist.Disconnect the battery (after putting the suspension in low and the car on axle stands) - there is a procedure in the C5 Technical section Common Problems pinned topic that can be followed. Remove :The front right wheelThe front right mud shieldThe 2 nuts holding the pump to the bodywork (1)The LDS fluid reservoir (to drain this the procedures say to Start the engine.Lower the vehicle to the low position.Stop the engine.Raise the vehicle and support on axle stands, wheels free. Undo the cap to release the pressure, remove the pipe under the reservoir). The reservoir is held by 2 nuts at the top which need removing so it can be removed. Disconnect the pump electrical connectors ( as "a", "b").Remove the protection from the ECU connector.Disconnect the pump electrical connector ( as "c").Uncouple the high pressure piping (2) (on each side). 3. RefittingCAUTION : Fill the LDS fluid reservoir with new liquid TOTAL LDS H50126. N.B. : Fit new seals where the pipes connect to the pump (3).Engage the BHI on its support.Couple up : The high-pressure pipes (2) ; Tighten the unions to 12 Nm.Reconnect the connector ( as "c").Refit the protection on the connector with a new zip strap ( as "c").Reconnect the connectors ( as "b", "a").Refit : The LDS fluid reservoirThe nuts (1)The front right mud shieldThe front right wheelTighten the wheel boltsReconnect the battery.CAUTION : Perform the operations to be carried out following reconnection of the battery.CAUTION : Use LDS fluid (new). To refill the reservoir -"b" LDS fluid maximum level - 2nd ridge from the bottom of the filling neck."a" LDS fluid minimum level - 1st ridge from the bottom of the filling neck.Fill the LDS fluid reservoir up to the maximum level of LDS fluid "b".4. BleedingApply a pressure of 0,5 bar in the LDS fluid reservoir (using a FACOM 920 tool) - instead of this, I have read on here that if the pump does not prime then covering the neck with polythene and blowing in through a hole in this may work or leaving overnight may work.Start the engine.Wait for the vehicle height to stabilise.Place the suspension height control in the "HIGH" position.Place the suspension height control in the "LOW" position.Turn the steering from lock to lock in each direction.Stop the engine.Check the LDS fluid level - with the suspension in the low position it should be at the maximum height b.N.B. : If the integrated hydroelectronic unit is replaced, configure the integrated hydroelectronic unit ; Using the [1] diagnostic equipment.

I think the pressure sensor is the part that is at the top left of the picture in the red area. The solenoid is not in the picture, to find this look at the turbo and on it will be an actuator with a small diameter plastic pipe, follow the pipe to the solenoid.