1997 MK2 Xantia 1.9TD, bypassing stop solenoid info needed

masood_ilyas · Post by **masood_ilyas** » 18 Sep 2007, 17:38

This concerns Citroen Xantia Mk2, 1.9TD model with remote RF transponder key.

Given the excessive stealer charges (£198) for remote key, data search and programming I have been toying with the idea of getting an ordinary copy for my key and bypassing the circuitry for the fuel pump's stop solenoid. This is in case I lost my only remote key so it could still be operated from a non transponder key.

Has any one explored the fuel pump stop solenoid on Xantias of the 97-99.
Mine seems to have it covered up as if one is not supposed to get at it.
One of the bolts is accessible whereas the other one has been blocked off, so how is one supposed to take it apart, can it be drilled out without much hassle?. has any one been here before. Is it worth pursing this line of thought.

Any ideas will be appreciated.

Masood ILYAS

Post by **CitroJim** » 18 Sep 2007, 19:24

Hi Masood,

Been there

My stealer quoted me £100 all-in for a new transponder key for mine

The following applies to a keypad rather than transponder Bosch pump. Fine detail may vary on yours but it should be applicable..

I don't recommend this just to save the cost of a key but here goes..

You are right in that the solenoid is protected by armour. Removing the armour to gain access to the solenoid is not a trivial job. It can be done but the pump must be removed from the engine. This is not a straightforward job either, you need a small puller to remove the sprocket from the pump shaft and a special spanner to get to the lower pump securing bolt.

Once you have the pump on the bench, you'll need to identify all the screws that secure the armour. Some are in fact ordinary Torx Screws and others are disguised as rivets. You need to drill these out. They are tight and hard and you need to be very accurate in drilling, using high-quality, sharp drills. One rivet/bolt is nigh-on impossible as it is deeply recessed and as hard as glass. It is in fact one of the distributor holding bolts. I wore out many drills trying and eventually, my very resoureful Dad use a masonary drill in a big hammer drill going backwards to jar it loose. Don't under-estimate the difficulty of this part of the job.

In doing this, you are getting quite brutal with the pump and damage is an ever-present risk, as is getting swarf into sensitive areas of the pump.

Once the armour is off, you can remove the electronics above and expose the solenoid. You then need to pick up an ignition-switched supply to operate it. This can be picked up in the ECU box as a supply from the twin relay. Wire 1288 is good.

You'll need to refit the armour and replace the butchered screws. The armour is necessary as part of it forms the rear mount for the pump.

I guess Bosch must have a way of getting the armour off a bit easier than we do as it is necessary to remove it for any repair work needed on the pump proper.

You say yours has a transponder? Take care to determine that the transponder receiver only locks the solenoid direct and does nothing clever to the ECU. These pumps will allow the engine to run with no ECU connected/working but the timing will be in "limp home" retarded and performance will be terrible. The ECU also runs the tacho and controls the glowplugs.

All in all, for all the difficulty, an easier (and cheaper) route is to get a second key cut. I know they're expensive but... The above is a LOT of HARD work.

I did this job to look at repairing a leaky pump and to fit a pro-tem fully mechanical pump in place of the semi-electronic one whilst it was under repair.

masood_ilyas · Post by **masood_ilyas** » 18 Sep 2007, 20:58

Thanks Citrojim.
Obviously the best thing would be to look after my Key,
You are right, it sounds like a lot of trouble for the price of a spare key.

Just as an exercise in exploring the options, how about doing away with the ECU and replacing the pump with older purely mechanical MK1 type which does not have the limp home mode. I bought one on Ebay for 1.9TD 94-95 Model, it is still greased and wrapped up some where in the garage.

Masood

Post by **CitroJim** » 18 Sep 2007, 21:22

masood_ilyas wrote:Just as an exercise in exploring the options, how about doing away with the ECU and replacing the pump with older purely mechanical MK1 type which does not have the limp home mode. I bought one on Ebay for 1.9TD 94-95 Model, it is still greased and wrapped up some where in the garage.

I have done precisely that Masood and I can confirm it works perfectly. In fact the owner of the car in question (a forum member on here) reckons it goes a lot better having a mechanical pump and I concur. After I swapped pumps, his car really flew.

Mechanically, it is a straight swap. all fuel lines swap over and the throttle cable inner just needs to be lenghtened by about an inch. The fast idle cable will go on with a different nipple fitted on the end. Connect the stop solenoid to wire 1288 in the ECU Housing.

Strictly, you need to arrange for the cold advance solenoid on the mechanical pump to be operational but in practice it makes little difference.

The only small problem is the ECU. Not only does it control the pump timing but it also runs the tacho and controls the glowplug operation, in particular post-heating, the latter being very critical on a cold Turbo XUD. I left the ECU in place to do these functions as the substitution was initially only temporary. The only down-side is the engine management light is permanantly on but a pair of cutters on wire 480 or removing the bulb will cure that

For a permanant installation and total removal of the ECU, you would have to rewire the tacho to work directly from the TDC sensor and you may need to change the tacho head for an early Xantia one to do this. You would also need to add and wire up the post-heating/cold advance control relays as used in the early Xantia with the mechanical pump. Luckily, this is all clear in the Haynes BoL circuit diagrams and is one of the only known accurate electrical drawings there!!!

So, in short, a straightforward swap. There will be no MOT worries either as only smoke is tested. If doing this as a permanant job it might be advisable to do away with the cat if it is still fitted as a mechanical pump will smoke a little more and may, in the long term, plug up the cat. A cat is not a legal requirement on a diesel in the UK anyway so no worries there

Nearly forgot, you need to time the new pump accurately as mechanical pumps have no external help from electronics to trim their timing. You can do a reasonable job by ear though and if the replacement is second-hand, you'll see marks from the nuts and washers that secured it to the original engine and these will give a good starting point for timing on your engine.

dnsey · Post by **dnsey** » 19 Sep 2007, 08:57

It would be a relatively simple matter to 'capture' the unlock code for the pump (at its connector), and build a small device to replicate it.
I'm reluctant to give any further details, as there's obvious potential for misuse, but I thinkyou'll see what I'm getting at...

citronut · Post by **citronut** » 19 Sep 2007, 09:26

bypassing shut of valve power can be done without removeing the pump from the engine, i have watched it done on a 406 pug, you need to cut into the metal cover with a small cut of angle grinder, firstly you need to locate were the steel roll pin lies in the metal cover plate, this is fitted from the rear face edge into a blind hole, so you cant just drift it out, you need to cut a slot into the plate running from north to south in the same line as the roll pin runs, once you have found the front end of the pin you can then drift it out, then undo the rest of the retainning fixings, once you have the plate out of the way you can run a swithched live from the glow plug timer to the solenoid shut off valve, it must be a live feed which is switched on/off with the ignition, the plate you remove also has the electronice bonded to the inside and this unit used to be around £170 sqide to replace
regards malcolm

Post by **CitroJim** » 19 Sep 2007, 12:40

Hi Malcolm,

That procedure is for the Lucas Pump I believe, In the Bosch I've attacked there was no roll-pin and the electronic module was not bonded to the cover.

I like your angle grinder idea but on the Bosch looks a non-starter because of how the armour is arranged. Bosch were quite switched-on in making it a mission to get past it. I's also be scared of grinding dust getting in the pump and doing damage.

It would be a relatively simple matter to 'capture' the unlock code for the pump (at its connector), and build a small device to replicate it.
I'm reluctant to give any further details, as there's obvious potential for misuse, but I thinkyou'll see what I'm getting at...

Interesting Dnsey. I can see exactly what you're getting at. A very good though and idea. Have you done this? No need for detail...

citronut · Post by **citronut** » 19 Sep 2007, 19:29

ok Jim
im quite sure there would be no were the grinder dust could enter the pump as there is no opennings whilst useing this method
regards malcolm

MikeT · Post by **MikeT** » 19 Sep 2007, 20:38

I'm not sure of the exact location you have to grind at but isn't there a vent/breather hole just above the armour? I have one but I'm not sure it's only for turbo versions of the pump.

Post by **CitroJim** » 19 Sep 2007, 21:32

I've been out looking again at my dismantled pump.

It would be possible to grind off the very front and top of the armour using a very fine Dremel-type cutter and expose the electronic module that clamps round the stop solenoid. It would be hellishly difficult though and I very much doubt it could be done with the pump in-situ.

Once the electronic module is exposed, it is held by two tamper-proof bolts that clamp the module via a bar around the hexagon of the stop solenoid. these bolts can be undone by jamming a hex (Allen) key into them.

I'll take a few pictures to show what I mean and post them up.

Malcolm, You're right about grinding dust when doing the job in-situ, yes there is nowhere it can get in.

Post by **CitroJim** » 19 Sep 2007, 22:00

Pictures:

The first shows the armour in place. The drilled out rivets can be seen.

The next shows the module above the stop solenoid after the armour is removed. You can see the two screws holding it.

Removing the screws with a Hex bit and spanner

And finally, the stop solenoid exposed.

If you carefully slice off the top and front of the armour it will be possible to withdraw the electronics and wire straight to the solenoid.

Note that the pump head is removed in these shots for clarity. The boost sense diaphragm housing and the fuel return line connection will considerably impede access when in place. On the bench it could be done with a Dremel but in-situ, I still think it would be close to nigh-on impossible unless you made a few well chosen cuts and then took a hammer and cold chisel to it

romie · Post by **romie** » 12 Jul 2010, 12:07

I've a Citroen Xantia 1996 1.9TD with Bosch fuel pump.

Fuel going to pump but nothing to injectors.

12v to pump and I can hear a click from where the stop solenoid is under the black plastic cased ECU.

Thinking stuck stop solenoid.

The 'Armour' that is shown above protecting the Stop Solenoid is not there but the black plastic ECU IS mounted on top of the solenoid with what looks like two shear off bolts holding it on.

I need to remove this ECU to get at the Stop Solenoid.

gripBolts were mentioned in another thread and I've asked on that thread if anyone knows the size of the gripBolt needed and whether the gripBolt will fit down the hole in the ECU?

I understand that this ECU is coded to the immobiliser module and so will need to be kind-of intact to still allow the immobiliser to disarm.

To get at the Stop Solenoid without removing the fuel pump I'll be looking at:
gripBolts, drilling out the what looks like shear bolts, small grinding bits on end of dremel, impact drivers with modified bits, hacksaws, welding rods and possibly a large chisel n hammer.

Has anyone else had any luck in removing just the black ECU covering the Stop Solenoid with different methods?

Many thanks

Post by **CitroJim** » 12 Jul 2010, 12:30

To be honest, the task of dearmouring the pump in-situ is really a non-starter. It is technically possible but fraught with many risks. I once saw the result of an in-situ dearmour and the engine was wrecked beyond belief following the ingestion of a piece of stray armour.

So, spend an extra hour removing the pump.

A bolt grip wont do as all but two of the tamperproof bolts are heavily shrouded.

I would recommend that you drill the bolt heads with a very hard (cobalt) drill bit to a suitable size for use with a good quality stud extractor of the internal variety. The problem is that you very carefully need to centre the drill on the bolt head and I'd recommend you knock up a drilling guide on a lathe for this. The one tamperproof bolt that is the most deeply shrouded is one that holds the distributor head and is made of high tensile steel; it is therefore very hard and beyond the wit of a normal drill bit. This bolt must be replaced later on with a Torx bolt of equivilent quality and length.

Another method of bolt extraction, after drilling a suitable hole in the head of the tamperproof bolt, is to use a hammer drill with a masonary bit running backwards in hammer mode. It works like an inmpact driver.

Huge care must be taken to avoid ingress of swarf into the pump so it is absolutely essential that all orifices are kept firmly closed. If you get new seal set this includes special protective caps for the orifices.

romie · Post by **romie** » 12 Jul 2010, 13:53

hey CitroJim, thanks for such a quick response.

The metal armour doesn't exist on my bosch pump.

I've only got to remove the two bolts holding the black ecu on that sits on top of the stop solenoid.

Using the picture above I've arrowed the two bolts I need to remove, but I think as the armour isn't there the bolts are of the shear off type.

Post by **CitroJim** » 12 Jul 2010, 14:20

Ahh, sounds like your pump has been previously de-armoured before romie. That makes it easier...

The bolts that hold the Immobiliser "lump" around the stop solenoid proper are tamperpreoof but they're not normally tight and a T25 or T30 Torx bit can be eased into them and sufficient purchase obtained to undo them.