Distributor Less Ignition retroFit?

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Tim Leech
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My Cars: 1963 VW BEETLE 1200 KGJ413A
1972 Morris Marina 1.8 SDL BFA720L
1979 Rover SD1 3.5 V8-S TSL 982
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C BXi 19
1994 CITROEN XANTIA 1.8 SXi M908HRY
2002 Rover 75 CDT Connossieur SE Nav Auto R40TSL
2002 Rover 45 1.6i Spirt S TAL 91S
2003 Rover 25 1.6i XL L33CHT
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Distributor Less Ignition retroFit?

Post by Tim Leech » Sat Jun 08, 2019 11:04 am

My 19TZI has normal electronic ignition with dizzy cap etc

I have noted a few other cars slightly later have distributor less ignition?

Is this plug and play,

My 1.8i 8V xantia has it also
1985 BX 19GT Mk1
1991 BX 19TZI Auto A/C
1994 Xantia 1.8i SX
1972 Morris Marina 1.8 SDL
1979 Rover SD1 V8-S
1980 Morris Marina 1.7HL
2002 Rover 75 CDTi Connossieur SE AUTO Nav
2002 Rover 45 1.6i Spirit S Special
2003 Rover 25 1.6i XL 5 DR
1963 VW BEETLE 1200

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Jaba
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Re: Distributor Less Ignition retroFit?

Post by Jaba » Sun Jun 09, 2019 9:24 am

Tim Leech wrote:
Sat Jun 08, 2019 11:04 am
My 19TZI has normal electronic ignition with dizzy cap etc

I have noted a few other cars slightly later have distributor less ignition?

Is this plug and play,

My 1.8i 8V xantia has it also


I am not sure Tim. If your ECU has a TDC sensor which sends a signal to the ignition amp and varies the timing according to the load then yes it can be done by swapping the HT coil pack for the dizzy.
Otherwise you will need the full conversion of ECU, loom and the rest to do a full 1.3 conversion from a donor with a CAT fitted (I think your TZi has a cat). In other words it is not worth the trouble for the small mileage your TZi does.
The Joy of BX with just one Citroën to my name now. Will I sing Bye Bye to my GTI or will it be Till death us do part.

Kaapelimies
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Re: Distributor Less Ignition retroFit?

Post by Kaapelimies » Mon Jun 10, 2019 3:46 pm

I'm quite sure it's not just about the TDC-sensor, as then the spark would come in all 4 cylinders at the same time and it wouldn't work very nice in the cylinder that is sucking in the fuel mixture.. You need the ecu and the wiring loom (and to have all components attached) also, which are quite an easy fit as they are all separated from other electricity in a BX. It's an easy weekend job.
BX 4x4 estate, several BX Van's and some more normal estates in Finland.

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Tim Leech
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Posts: 15135
Joined: Tue Apr 15, 2008 11:12 am
Location: Burton on Trent
My Cars: 1963 VW BEETLE 1200 KGJ413A
1972 Morris Marina 1.8 SDL BFA720L
1979 Rover SD1 3.5 V8-S TSL 982
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C BXi 19
1994 CITROEN XANTIA 1.8 SXi M908HRY
2002 Rover 75 CDT Connossieur SE Nav Auto R40TSL
2002 Rover 45 1.6i Spirt S TAL 91S
2003 Rover 25 1.6i XL L33CHT
x 54

Re: Distributor Less Ignition retroFit?

Post by Tim Leech » Tue Jun 25, 2019 2:26 pm

Ahh ok I will leave as is!
1985 BX 19GT Mk1
1991 BX 19TZI Auto A/C
1994 Xantia 1.8i SX
1972 Morris Marina 1.8 SDL
1979 Rover SD1 V8-S
1980 Morris Marina 1.7HL
2002 Rover 75 CDTi Connossieur SE AUTO Nav
2002 Rover 45 1.6i Spirit S Special
2003 Rover 25 1.6i XL 5 DR
1963 VW BEETLE 1200

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Way2go
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Re: Distributor Less Ignition retroFit?

Post by Way2go » Wed Jun 26, 2019 5:34 pm

Kaapelimies wrote:
Mon Jun 10, 2019 3:46 pm
I'm quite sure it's not just about the TDC-sensor, as then the spark would come in all 4 cylinders at the same time and it wouldn't work very nice in the cylinder that is sucking in the fuel mixture.. You need the ecu and the wiring loom (and to have all components attached) also, which are quite an easy fit as they are all separated from other electricity in a BX. It's an easy weekend job.


The system (or principle) is actually know as "Wasted Spark" which if you think about it does not conflict with the induction stroke as that is paired with a power stroke for which the spark has occurred just before TDC (ignition advance).

However this system, the Motronic 3.1 used on the later GTi 8v does not use a vane air meter to calculate fuel demand but the more advanced MAP sensor (Manifold Absolute Pressure). There is usually no cat involved for uk BXs except for possibly their last number off the line.

Clearly the BXs used different ECUs or at least different firmware within them to support the various types of Motronic (or the earlier Jetronic) ignition and injector systems.

I guess it is questionable on the perceived worth of doing the upgrade but the MAP sensor does give a better driving sensation as acceleration is immediate and more powerful being without the lag associated with the mechanical air meter. With improved spark efficiency too I feel that Motronic 3.1 gives a great performance advantage and was a positive upgrade by the Citroen Designers. :D
1991 BX19GTi Auto