After a spell of good behavior 'Red Simon' (2.5 diesel estate) developed a loud graunching noise from somewhere on the front offside last Friday. Cannot identify the exact location yet but looks like it might be under the wheelarch (!).

It Happens when I turn on the ignition (not the engine) and the noise remains constant whatever the road speed. There was also a slight hot electrical smell.

Before I start ripping things apart, has anybody experienced this problem before?

The vac pump is on the outside of the chassis, offside forward of the front wheel.
Cannot think of anything else ignition controlled in that area.

John

Many thanks, looks like the vac pump is the culprit.

Never to old to learn. Three XM's from new and I did'nt know it lived there! Next challenge is to find a replacement. Any idea if it is common to any other Citroen vehicles?

Kevin

If its the same as the vacuum pump on the 2.1 I'm breaking one at the moment.personally id blank off the egr!
Dave

Hi Dave

I suspect in the ideal world I would also rather blank of the EGR. However, I have been told by those more learned than I that the process is not as straightforward in the later 2.5's as it is in the earlier spec cars.

Apparently, in an attempt to meet ever tighter emmision regs both the EGR and EMU were modified in late 97 and blanking of the EGR causes a dashboard full of lights and occasionally a reversion to safe run mode. Happy to take advice but that is what I have been told.

Not sure whether the 2.1 and the 2.5 vac pump are common but the part number I am seeking is 00001628R2. Would be interested in yours if compatable

Regards

Kevin

The 2.1 bosch is a much simpler beast! Sounds like the egr is best left alone! I will try and find out tonight about the part number!

The only connection between the Vac pump and the engine is the vacuum tube.
So a 2.1 pump should do fine.
You are right that the later 2.5's have a load more emissions crap added.
It stops the ECU's being swapped.
Until last month I had no spare late 2.5 ECU's so was going to convert a late engine to early spec.
Then Bosch Germany remaindered some NewOldStock late 2.5 ECU's on ebay.

John

I have not managed to get the one off the car I'm breaking, but have found the one that I removed from my own car.



I will PM you.
Dave

Don't most XUD diesel engines have a vacuum pump driven from the end of the camshaft rather than electrically? My 2.1TD certainly does and so did my old 1.9TD ZX (for the brake servo).

Ken

Hi Ken, only on XUDBTE engines fitted to Xantia, XM & Synergie.
robertm

Ken,

DONT get mixed up.. Theres NO Vaccuum pump on the earlyer TD XM because they are power brakes.. A vac pump was only added on the cam for the Vaccuum operated electro valves etc..

The Other vaccum pump in the wing is just for Emmissions...

Is that Correct, or am I mistaken too??

You'll only finf the "Wing Mounted" Vac Pump on cars with EGR's, from around 1992 onwards.

My 1991 H reg SED 2.1 has neither an engine Vac Pump or a inside Wing Pump, as it has no EGR..