speed limited Xantia

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Stewart(oily)
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Joined: 07 Oct 2005, 16:31
Location: North Wales
My Cars: Citroens since 1990, BX Diesel, GTI, TZD with 1.9 TD running extra boost before it was fashionable!, ZX Volcane TD, S2 Xantia break 1.9TD, Xantia HDI 110, currently zipping about in a C2 Diesel. C2 died from the dreaded worm, C3 Picasso HDI Exclusive, the adventure continues.
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speed limited Xantia

Post by Stewart(oily) »

hello all, my HDI 110 Xantia has put its engine light on again, both times have been at about 75mph with my foot well down asking for more power, it goes into reduced power limp mode and then the fault goes away after a couple of restarts, I am thinking of swapping the electrovalves over for a start, anyone had similar ?
BXs since 1993 built 1.9 TZD turbo, got a S2 Xantia estate, brilliant car! 2013, Xantia HDI LX 110 2000 new car with 122,000, l C2 HDI Rusty rocket, C3 Picasso HDI new to me.
Chlorate
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Re: speed limited Xantia

Post by Chlorate »

Yep mine did that not long ago.

I fitted a new electrovalve after a secondhand one didn't seem to do the trick, and funnily enough it did it again!

I think I found Euro Car Parts to be the cheapest nearby stockist of the electrovalve in question.

I suspect in my case there's a fault in the connection between the ECU and the electrovalve, momenterily the signal to the valve drops, the wastegate opens, boost drops, ecu gets upset and slams on limp mode. After a jigger of the wire and a restart the valve wakes up again and we're back to normal.
Hasn't done it again for a couple of months.

Had a Lexia on it? The fault on mine actually specifically said electrovalve next to boost pressure too low.
Citroen Xantia Exclusive HDi

previously:
Citroen ZX Volcane - RIP
Peugeot 106 XN... stolen and destroyed by Kent Police :evil:
Stewart(oily)
Posts: 893
Joined: 07 Oct 2005, 16:31
Location: North Wales
My Cars: Citroens since 1990, BX Diesel, GTI, TZD with 1.9 TD running extra boost before it was fashionable!, ZX Volcane TD, S2 Xantia break 1.9TD, Xantia HDI 110, currently zipping about in a C2 Diesel. C2 died from the dreaded worm, C3 Picasso HDI Exclusive, the adventure continues.
x 31

Re: speed limited Xantia

Post by Stewart(oily) »

So I will swap the electrovalves over, electrical and Vac connections and see if it makes a difference, the EGR one doesnt do a lot since I shoved a bolt up the pipe :) convenient of them to fit a spare.
BXs since 1993 built 1.9 TZD turbo, got a S2 Xantia estate, brilliant car! 2013, Xantia HDI LX 110 2000 new car with 122,000, l C2 HDI Rusty rocket, C3 Picasso HDI new to me.
Chlorate
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Joined: 25 Sep 2009, 00:55
Location: Wiltshire
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Re: speed limited Xantia

Post by Chlorate »

It's also worth removing the vacuum "feed" hose that connects the pump to the electrovalves to make sure that its not blocked up. You can also disable the EGR by removing the t-piece from that pipe and connecting the hose directly to the wastegate control electrovalve :twisted: Does exactly the same thing.

If swapping the wastegate and egr electrovalves doesn't work, don't worry it's not unheard of for both valves to have died.
Citroen Xantia Exclusive HDi

previously:
Citroen ZX Volcane - RIP
Peugeot 106 XN... stolen and destroyed by Kent Police :evil:
Stewart(oily)
Posts: 893
Joined: 07 Oct 2005, 16:31
Location: North Wales
My Cars: Citroens since 1990, BX Diesel, GTI, TZD with 1.9 TD running extra boost before it was fashionable!, ZX Volcane TD, S2 Xantia break 1.9TD, Xantia HDI 110, currently zipping about in a C2 Diesel. C2 died from the dreaded worm, C3 Picasso HDI Exclusive, the adventure continues.
x 31

Re: speed limited Xantia

Post by Stewart(oily) »

Electrovalve swapped, tee piece removed, light out and performance more than restored :)
I have only done 700 local miles with this car and was beginning to wonder what all of the HDI 110 fuss was about, now I have full power 8-)
BXs since 1993 built 1.9 TZD turbo, got a S2 Xantia estate, brilliant car! 2013, Xantia HDI LX 110 2000 new car with 122,000, l C2 HDI Rusty rocket, C3 Picasso HDI new to me.
Chlorate
Posts: 612
Joined: 25 Sep 2009, 00:55
Location: Wiltshire
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Re: speed limited Xantia

Post by Chlorate »

Good stuff :-D

The 110 HDi is a surprisingly good engine to drive.
Citroen Xantia Exclusive HDi

previously:
Citroen ZX Volcane - RIP
Peugeot 106 XN... stolen and destroyed by Kent Police :evil:
citroenxm
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Re: speed limited Xantia

Post by citroenxm »

Nice one. You have solved what exactley i was going to tell you what it was..

As for info the system actually works in reverse.. the waste gate with no vaccumm is actually wide open. When the engine starts the vaccumm is applied to the waste gate contantly.. and closes it to allow boost. Then the electro valve works in reverse and when boost pressure is reaching the electro valve drops the vaccumm to the valve then allowing the waste gate to open..

For some time i beleved it worked the other way around like older turbos.. but they dont. This is prooved by having no boost when theres no vaccum. The ecu is happy with low boost .. no damage can occur but with over boost there is a chance so it cuts the engine into limp. So what useually happens is the electro valve sticks on vaccuum applied to the waste gate ...and keeps the gate closed...
Sharing a pug 207 1.6 hdi Sw 16v.
M reg Xm 2.1 td auto exclusive S2 269k and rising
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Chlorate
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Location: Wiltshire
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Re: speed limited Xantia

Post by Chlorate »

Let's not forget Paul it was you that told me what it was when it was my turn :wink:

It is a bit of a strange system, but it does make some sense.
Controlling the wastegate from the ECU needs some other kind of actuation than what you see in older systems (like the turbos on XUDs use pressure from the compressor side to open the wastegate via an actuator when it gets to the limit). A lot of other cars use a hefty solenoid directly on the wastegate lever, I think in this case they had the foresight to realise that if it ever failed it would be a right 'mare to switch out and would require a decent amount of current to power. Since the engine is fitted with an, otherwise unused except in lesser cars, vacuum system it makes no sense not to put in a little actuator that switches the vacuum in and out.

Keeping it open until the vacuum closes it is a neat idea as a safety feature to prevent boost creep or overboost if there's any problems with the engine management.
Citroen Xantia Exclusive HDi

previously:
Citroen ZX Volcane - RIP
Peugeot 106 XN... stolen and destroyed by Kent Police :evil:
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