Bosch diesel fuel pump

Post by **KennyW** » 20 Mar 2009, 20:54

Hi Gang,

My bosch pump is not pumping through fuel under pressure into my injectors.

Does this mean removing pump and overhauling it to fix problem

Kenny

Post by **Peter.N.** » 20 Mar 2009, 21:55

The most likely cause is that the solonoid fuel valve is not opening. If its an earlier car without a key pad this is quite an easy problem to solve as you can gain access to the valve, its at the back end of the pump just above where the injector pipes are fitted. You will see a small screw terminal with a wire connected to it, check for 12 volts with the ignition on.
If the voltage is there, the valve itself is probably faulty. To check, unscrew it and remove the small plunger and refit, if it runs OK now, replace the valve or you wont be able to stop it!

If you have the later type pump the solonoid is in a sealed compartment, very difficult to get at and will need the pump removed to even try.

I assume that you have checked the fuel feed to the pump as OK?

Post by **CitroJim** » 21 Mar 2009, 17:40

I would very much concur Peter. there is little or nothing inside the Bosch that can cause a total lack of injection unless something in there has failed very catastrophically and that's very rare. Even with a broken HP pumping element plunger return spring they'll still pump a bit.

If not the solenoid then it's very likely to be an immobiliser problem. Is this on a MK2 Xantia with the RFID key Kenny?

Post by **KennyW** » 21 Mar 2009, 20:33

Thanks for the replies,

If i crank the engine over for at least 20 turns or there about it will start,hence i think it is a problem with the pump ie no fuel being injected at pressure.

It all started when i had to change the ignition barrell for a new one and the key coding took longer than expected.

My Xantia is a mk 2 with the immoboliser built in to the ignition barrell.

Kenny

Post by **CitroJim** » 21 Mar 2009, 20:51

Does it start and run fine after 20 trurns Kenny? If it does then no real problem par-se with the pump.

Is the key in lock light (orange symbol on tacho) going out immediately?

Is the start accompanied by clouds of smoke? And if so, what colour?

A co-inciodence maybe but I'd be looking at glowplugs or the usual causes of poor starting on a TD before condemming the pump or immobiliser at this time. Even when warm a TD needs all for glowplugs to be in good order to ensure a good start...

Post by **Peter.N.** » 21 Mar 2009, 20:53

I doubt if its the pump, is it a Bosch? Sounds as though either the glow plugs are not working or its sucking in air somewhere.

Post by **KennyW** » 22 Mar 2009, 22:43

Thanks for the replies,

I changed the glow plugs as they were about 2 1/2 years old.

It is a Bosch diesel pump. The pump runs fine when going.

There is no obvious sign of an air leak, no signs of bubbles in the clear plastic tubing from the fuel filter to pump. I was tempted to change the fuel pipe from the bubble primer to the fuel filter and plastic tubing from filter to pump.

Any suggestions or ideas gratefully accepted.

Kenny

Post by **Peter.N.** » 22 Mar 2009, 22:50

Have you checked for 12v on the glowplugs? Still could be the solonoid sticking, try temporaraly removing the needle - if its not a keypad type.

Post by **KennyW** » 23 Mar 2009, 09:15

Thanks for the reply Peter,

Unfortunately my Bosch pump has the armour surrounding the Solenoid, so I'll test the Glowplugs first

After that I think i'll have to take it to a specialist.

Kenny

Post by **Peter.N.** » 23 Mar 2009, 09:26

Oh dear

Connect a meter between any glow plug connection and earth and put it where you can see it from inside the car, should read 10 -11 volts for about 15 or 20 seconds after switching to glow plug position.