Lokiel wrote:I did a quick Google on this issue this morning and the answer was obvious - our cars use Wasted Spark ignition so there are 2 sparks per rotation, which is why the timing light reported double the RPM rate (cylinders 1&4 and 2&3 are ignited at the same time).
Not sure why Ignition wire 2 was always reporting the correct RPMs, it should have behaved the same as Ignition wire 1.
That was what I infered, and I can only guess that there was interference of some sort with the clip on lead #1 as it was also touching the cam cover, whereas when Vat put it on #2 it was resting on lead #1...?