I have a good fat spark on start up and tickover and for normal pottering, but the harder the engine revs, the weaker the spark gets until it breaks down and the engine starts to miss. It will keep going but is just not happy and having had a spark tester on it while revving you can see the spark get weaker and weaker as the revs rise higher and higher.... anyone got any ideas what could be causing this breakdown? So far i have changed the ignition amp for a known good one and fiddled about swapping components, but nothing i have swapped has made a significant difference. It seems that the breakdown is in the HT side, as the injection seems to keep working fine and this is taking its signal off the LT side, but any thoughts from you guys are welcome.
![Confused :?](./images/smilies/icon_confused.gif)