406

[Mbryn1]

So do I go for a lift pump

[Peter.N.]

If I had metal particles in the fuel system I would before it does more damage.

[BX]

Tick over ok. Can Run all day. Cuts out when driving. Can be restarted after a short period. Possibly runs on slightly when the ignition is turned off. Anti pollution on the dash. These are typical of a blocked high pressure regulator. It is fastened to the end of the hp pump with two T30 torx screws. The topic has been covered several times on these forums.

Peter N has been through it all. I'll let him explain.

Probably better renew the lift pump as well if there are a lot of filings in the filter housing. When doing this disconnect the fuel lines and blow them out. Make sure that the fuel filter housing is properly cleaned and the new filter properly fitted.

[Peter.N.]

As BX says, but the lift pump will probably be the cause of the blockage so you need to change that before you change the regulator. Some regulators don't have a filter so you can grind the end off it instead of replacing but make sure you get rid of any swarf.

Peter

[Gibbo_Wirral]

I'm sure I told the OP to check the lift pump on another forum, over a week ago.

[Peter.N.]

You probably did, his posts are popping up everywhere.

Peter

[Mbryn1]

Lol honest John by any chance day off thinking about it today but I'm going to check the lift pump and regulator I heard you can grind the end off the regulator is this true

[Hell Razor5543]

Something you might want to think about is that the filter is doing its' job. It has stopped those filings getting into the HP pump. According to the Haynes BoL the HP pump is very sensitive to dirt, so it is vital the fuel getting into it is kept clean. If the filings get into that pump it is likely they will write it off.

If you think about it, the lift pump is quite a coarse pump, and it doesn't need fine tuning. All it does is to get the fuel heading towards the engine. As it starts to wear it will 'slop' about, wearing out more quickly. This is probably where the filings are coming from. Due to its' simplicity it doesn't immediately fail, so it will continue to produce the filings until it is so 'sloppy' it will lose pressure. If you look around on the forum the general consensus is that if you find the filings in the fuel filter it is time to replace the lift pump before it causes any expensive damage.

Some regulators have a fine filter on them, and (based on what I have read on this forum) it is this you grind off. Be careful how you treat the regulator. A major contributor here had a long standing problem with his Xantia cutting out at inconvenient times. After a lot of 'try this, nope, try that, nope, drat it' he found it was a regulator, and that he had previously fitted one he thought was OK.

[Mbryn1]

Thanks did not think it could be hp pump as the car still starts drives for a little while surely if the hp pump had failed the car would not run at all as the lift pump would not pump fuel all the way to the engine right or wrong but The garage told me it was hp pump

[Hell Razor5543]

I don't know what pressure the HP pump generates, but I believe it is well in excess of 200bar. It needs, therefore, a good supply of fuel coming in.

[citronut]

is it possible to just replace the actual pump that is inside the lift pump unit,

as i did this on a Festa a couple of years ago at a fraction of the cost for the complete unit, and it was a very easy job

[citronut]

The garage told me it was hp pump

as James rightly says it can not be the HP pump causing the fillings in the filter, as the flow of fuel to the pump goes through the filter before it get to the HP pump,

but if you do not stop the fillings entering the system, some particals will pass the filter and destroy the HP pump,

the fuel cannot re/enter/go back into the filter once it has reached the HP pump,

the fillings have got to be coming from between the tank and the filter,

[Gibbo_Wirral]

I'd consider getting a Planet diagnostic. I've done a couple of 306s and 406s with similar problems and Planet has been brilliant at showing where the problem lies.

[Mbryn1]

Ok anyone got a cheap lift pump please

[Hell Razor5543]

Try asking citroenxm. He has a load of various bits (mainly for Citroens), and it is possible the lifter pump for a Xantia is the same as that for a 406.