couple of HDI engine questions

[Floodys]

Hi, can someone confirm first that a part on my 110HDI is a throttle body, its basically a plastic part bolted to the metal turbo hose to the right of the engine cover, held on by 2 10mm nuts, then the rubber intake hose is clipped to it, it has a flap inside and a vac hose leading off, i know its sounds like i havent got a clue to do with cars but i do! but ive always had petrol pugs and never really got involved with dirty dervs although had a 90HDI 306 and my 110 406 for years now and as we know they rarely miss a beat! basically, if it is whats called the throttle body, it leaks a smal bit of oil from the bottom and onto the head of the car, is this right plus there is obv oil inside the rubber pipe, turbo pipes etc, and i notice the bottom of the intercoler is leaking/has oil on it, at some point i will change the intercooler as i guess its fubar! so, should i have oil in the pipes, should the throttle body leak and if so can it be fixed or is a new part?

following on from the above if anyone reading has a intercooler in GWO and or a throtle body ill be interested!! ian

[steve_earwig]

Hello. Erm, the 2.0 HDi doesn't have a throttle body, I'm not really sure what you have there, it could be the mass air flow meter or the dozer (if your car has one of those). A small amount of oil will make it past the turbo seals but large amounts might be something more serious (but the cloud of black smoke following you down the road should give you a clue too). I think some have had problems with leaks, I remember someone a while back but I can't find it with a search but hopefully someone else will have a better idea

[Floodys]

no black smoke! no smoke at all! she is a clean runner! i was unsure as to why this bit i have has been refered to as a throttle body!! funny thing is that if i search for a throttle body for a hdi on ebay one comes up and it looks just like the part im talking about!!

[Floodys]

found out its a "air doser" anyone know what its is/dos?????

[martint]

From another forum:
It's like a throttle butterfly. Idea is to meter the quantity of air going in to reduce NOx emissions.

[puggy]

It is indeed the air dozer and it is a common fault for it to leak a small amount
of oil onto the head , this gives the impression of a fuel leak or the rocker cover
is leaking . What steve says about oil in the pipes covers the rest .
You could take it off and clean it then put some sealer around it .

[Busman]

It is indeed the air dozer and it is a common fault for it to leak a small amount
of oil onto the head , this gives the impression of a fuel leak or the rocker cover
is leaking . What steve says about oil in the pipes covers the rest .
You could take it off and clean it then put some sealer around it .

Thats what happens with mine. I find that taking it off and cleaning it every few months solves the problem. Takes about 20 mins to do.
I've been thinking about getting a new one, but I think that the problem will just happen again. Possibly taking off all the air pipes, intercooler etc. and cleaning them might help. And resealing it is more difficult than I thought, as the oil seems to be leaking from the shaft that moves the butterfly valve, not the o rings on the end.
Not a problem my wonderfully simple D8 suffers from!!

[grasmere59]

My old 2002 110 rapier had an air doser and that had a small leak but my 2003 110 executive doesn't have one,don't know why they stopped fitting them.I only have 2 vacuum valves on the bulkhead when the Rapier had 3 so i suppose the other valve was for the doser.the one thing i will say is that the Rapier smoked when given a bootfull and went really well but the Executive hardly smokes at all but doesn't go as well as the Rapier did.

[Welly]

According to The Citroen Xsara Owners club:

I've have run mine with this butterfly valve working and with it disconnected and I can't say it really made any difference to the shut down. Later models dispensed with it altogether, HDi 110s built from RP number 9611 onwards don't have it anymore.
I think its primary purpose was to balance the intake air between fresh air and EGR gas.
By shutting it would force the engine to draw in a greater proportion of EGR gas, and vice-versa.



Source: http://www.cxoc.net/index.php?PHPSESSID ... chju3hupb2&