timing shifting on cranking

hey guys,

today i got my car to the point where i was going to set the ignition timing after installing a haltech ps1000 onto my fj20 turbo. the trigger setup consists of a 12 tooth wheel on the crank and a single tooth home trigger in the dizzy, both running gt101 hall sensors. ive disabled the injectors, set the timing lock to 10 degrees then worked out the offset by measuring the circumference of the balancer then measuring the distance from when the home trigger reads etc etc... however the timing not being right on the money isnt the issue, whilst cranking i noticed that the timing is shifting, one minute theres nothing, thin you can see the pointer come up then off it goes again. any ideas would be muchly appreciated.

have you got the setting right for the 12 tooth wheel correct? is there any missing teeth on it?

To add to Chris's question, during cranking are you seeing consistent and regular engine speed shown on the laptop screen? On your diagnostics screen what is the miss counter showing? It's normal for this to show a value of 2-3 for example when you first crank the engine but it shouldn't continually increment.

im yet to get back to it to check, one other thing i noticed is that it intermittently stops sparking all together then the light gives a single flash once cranking has stopped.

do you have your timing light hooked up on on of the ignition leads or some inductive wiring loop? Make sure, it's hooked up directly on an ignition lead, and if you're running COPs use an old ignition lead, cut it on the dizzy side and put it in the coil and then your spark plug. works like a charm ;)