Xantia - Broken ignition coil suppressor capacitor

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lancia58
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My Cars: Xantia 2.0 16V Automatic make year 2000 LHD
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Xantia - Broken ignition coil suppressor capacitor

Post by lancia58 »

Hi

Just found out that the coil suppressor capacitor is broken. I can switch on the engine and drive and actually didn't feel any change. I had a post in which I told that there is a smell of petrol coming from the muffler and an HC of 130. I remember that in the old ignitions systems it was connected across the platinum contacts of the contact breaker by that improving the efficiency of the coil and prevents pits of these contacts. In the current electronic ignition there isn't any contact breaker but I wonder if the ignition sparks are weaker if this capacitor is failed, causing misfire that resulted in excessive fuel consumption, petrol smell and high HC. The capacitor is part of the coil pack harness and I cannot find it's value i.e. is it 2.2uF or what? Is the ignition coil harness part of the ECU harness ? Is it a separate harness ? If yes what is Citroen part number ? Can it be swapped with any contact breaker capacitor ? Hope these are still available.

Thanks
Zohar
Xantia 2.0 16V Automatic make year 2000 LHD
Citroen C4 THP Automatic make year 2009 LHD
Citroen C4 VTS 2.0 16V make year 2006 LHD
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Mandrake
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Re: Xantia - Broken ignition coil suppressor capacitor

Post by Mandrake »

The suppression capacitor on a modern ignition system is just a filter capacitor connected to the common positive feed of the coils. It doesn't serve the same function as a points capacitor on an old Kettering system.

A Kettering system won't work properly without the points capacitor, but as you've noticed you won't really notice any difference with it broken except maybe some interference on your radio.

Generic types are available and the precise value is not critical - typically about 2.2uF. The main thing is the voltage rating should be at least 100 volts and it should be rated at at least 100 degrees C.

You won't be able to buy one separately from Citroen, here is a suitable replacement that I fitted on my Xantia when the original capacitor broke in half:

http://www.thetoolboxshop.com/0-646-22- ... -5139.html" onclick="window.open(this.href);return false;

You can see some pictures here of the old and new capacitor on mine:

http://www.frenchcarforum.co.uk/forum/v ... 51#p378851" onclick="window.open(this.href);return false;

I very much doubt the capacitor has any effect on your high HC reading.
Simon

1997 Xantia S1 3.0 V6 Auto Exclusive in Silex Grey
2016 Nissan Leaf Tekna 30kWh in White

2011 Peugeot Ion Full Electric in Silver
1977 G Special 1129cc LHD
1978 CX 2400
1997 Xantia S1 2.0i Auto VSX
1998 Xantia S2 3.0 V6 Auto Exclusive
lancia58
(Donor 2022)
Posts: 711
Joined: 30 Nov 2010, 07:02
Location: Israel
My Cars: Xantia 2.0 16V Automatic make year 2000 LHD
Citroen C4 THP Automatic make year 2009 LHD
Citroen C4 VTS 2.0 16V make year 2006 LHD
x 8

Re: Xantia - Broken ignition coil suppressor capacitor

Post by lancia58 »

Hi Simon

Thanks for the info. I know that in electronic ignition systems a transistor is used as a "contact breaker" so no problem of the pits contact. I'll try to see if I can source this capacitor. The reception in the car's radio is without any interference so I guess it idoes not effect the reception quality too much. Anyway if I succeed in sourcing it I'll replace it. I keep the car in near prefect condition as much as I can. BTW the capacitor lead you used is heat resistant ?

Thanks a lot
Zohar
Xantia 2.0 16V Automatic make year 2000 LHD
Citroen C4 THP Automatic make year 2009 LHD
Citroen C4 VTS 2.0 16V make year 2006 LHD
User avatar
Mandrake
Posts: 8615
Joined: 10 Apr 2005, 17:23
Location: North Lanarkshire, UK
My Cars:
x 664

Re: Xantia - Broken ignition coil suppressor capacitor

Post by Mandrake »

The capacitor comes with a built in 100mm fly lead, and the other half of the lead (to the left of the red joiner) is half of the original capacitors wire which is moulded into the plug. I don't see any deterioration of the wire in the time it has been fitted.
Simon

1997 Xantia S1 3.0 V6 Auto Exclusive in Silex Grey
2016 Nissan Leaf Tekna 30kWh in White

2011 Peugeot Ion Full Electric in Silver
1977 G Special 1129cc LHD
1978 CX 2400
1997 Xantia S1 2.0i Auto VSX
1998 Xantia S2 3.0 V6 Auto Exclusive
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