G'day

My sunny seems to do this thing every now and again where i turn the ignition off, and the car suddenly fires up again for about 2 seconds and revs up real high before cutting out.
Im not too sure on what the problem is, would appreciate any help ;)

That's weird. Revs up real high can't be caused by a timing problem. Too far advanced timing can cause engine run-on but that is a very slow engine speed (below normal idle speed).

To cause your symptoms it needs 1) spark and 2) air. What could cause it?

dieseling?

Dieseling (engine run-on) is a very slow engine speed.

One of the most common causes of "running on" is a high carbon build up in the combustion chamber which at times the carbon glows red hot and acts as a ignition source even when the ignition is turned off, the engine usually chugs along at slow revs for a few seconds then stops or will actually run backwards at a higher RPM just prior to stopping, check your plugs to make sure they are clean,there are products you can spray into your carb or add to your fuel tank that will breakdown the carbon,you will see a lot of brown crap coming out your exhaust when you use it, or pull the head off and de-coke it
Russ

Yeah, it must be a problem in the carb. I inspected the engine after it happened last time and notice the left throat was all black, like it had carbon up the throat and over the top into the air filter. Bought some valvoline valve and carb cleaner to pour in the petrol tank and changed the air filter. Ill let ya know if it helps