No spark

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nathan5346 said:
The coil packs each have two wires connecting to the main plug am i right in thinking these two wires provide a 12v supply when the ignition is on? Does the ecu controll the power to the coil packs? if so would all coil packs be controlled by the same thing or would it be 1 for each coil pack?.. hope that makes sense cos i dont know what im on about :)
Click to expand...

Don't quote me on this, but as i understand it. The coils are charged to around 400volts by a capacitor this induces a current in the secondary windings of around 40K volts the ECU switches off the capacitor to fire a cylinder and the induced voltage is discharged down the plug lead. Exactly the same as the old points opening and discharging the induced voltage on and old coil system except that the ECU replaces the points as a switch. Because of the capacitor charging the coils a much higher voltage is avilable for spark. 25,000 volts old system 40,000 volts CDi system. The only reason anythig burns out is heat so that would suggest to me that the primary voltage is too high. How i don't know but that's my bit done.
 
wammers said:
Don't quote me on this, but as i understand it. The coils are charged to around 400volts by a capacitor this induces a current in the secondary windings of around 40K volts the ECU switches off the capacitor to fire a cylinder and the induced voltage is discharged down the plug lead. Exactly the same as the old points opening and discharging the induced voltage on and old coil system except that the ECU replaces the points as a switch. Because of the capacitor charging the coils a much higher voltage is avilable for spark. 25,000 volts old system 40,000 volts CDi system. The only reason anythig burns out is heat so that would suggest to me that the primary voltage is too high. How i don't know but that's my bit done.
Click to expand...

Extra to this and i don't know how i missed it the first time is. Yes the coils are energised the whole time, it is only when supply is switched off momentarily by the ECU that they discharge into the plug lead. This is done by the ECU in the correct firing order. They are then switched back on again to recharge from the capacitor.
 
Thanks for the advice, Spoke to RPI this morning and was told it will not be ecu related and that its definately a dead coil pack.... So to save spliting the packs up AGAIN i swapped the wires underneath to test the one that wasnt firing and swapped the ht leads to suit... Fired on all pots :confused: so swapped it all back round again and its running great as it should... conclusion? no idea maybe a bad earth/connection? cant fathom out why it burnt 2 coil packs out other than the above mentioned :confused: just hope it continues to run as it is... having the cats fitted this afternoon hopefully then book it in for MOT.
Thanks again for the help lads and the ones who PM'd :)
 
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