Exhaust gas recycling system, Sketch wanted

[techmanagain]

Can anyone owning a 2.5TD help me with a sketch - however basic - of the connections and locations of the tangle of pipes for the EGR system around the area of the accelerator potntiometer and engine top mount. A photo or two may help as well. (and yes I know that there should be notes made st the time of dismantling!) There is any awful lot of something wrong as limp mode is often the result every so often, as is the expulsion of a great cloud of black ssmoke before it will run smoothly again.
Any tips at all will help. Brian

[xmexclusive]

Hi Brian

There are two different versions.
Need to know the ECU type or ORGA to check.
Have some photos somewhere that I took when sorting out John Wilsons car.

John

[noz]

Hi Brian,

Please find atached the exploded diagram from Citroen Service. Hope it helps.

Unless you have a strong moral reason to reconnect it my advice would be to leave it disconnected. The entire principle of EGR only works as planned when the engine is new. Once all the component parts begin to wear the EGR starts to work against you. Feeding gases back from the exhaust into the intake manifold brings with it the volatile condensibles entrained in the air. These condense on the relatively cold surfaces of the inside of the intake manifold thus coating the surface in thick gooey tar. The additional resistance reduces the volume of air which can be taken in by the engine thus strangling performance.

The EGR valve is normally closed and thus requires the vacuum to open it. If the vacuum is disconnected the valve will remain permanently closed.

There is a slight warning to go with that philosophy. My father had an Audi A6 and to cut a very, very long story short the disc inside the EGR valve corroded through and therefore the valve was permanently open. The valve, if working correctly should only open when cruising at light throttles. Having a permanently open EGR valve meant that starting in the morning was very difficult and performance was severely degraded. Eventually he inserted a blank in the form of a piece of steel plate between the flanges and all his problems disappeared.

Cheers

noz