The timing can only be set to the base timing whilst at idle to enable the static timing to be adjusted using a timing light and by altering the position of the distributor. When the ECU reports timing it assumes that the base timing is correct, if you set base timing to 10 degrees then the ECU will still report 8 degrees.
The tool will report the values that the processor reads, if there is internal damage then the value could be skewed by that, I have had ECUs that have been damaged when a vehicle has been welded without the battery being disconnected and that damage has caused the ECU to read incorrectly. You can get a phenomena called 'parametric shift' where a component doesn't fail completely but its value is changed, this can also be caused by electrostatic discharge but the ECU does have some protection against that.
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1984 Suzuki SJ413K pick up, 1.6 16V Baleno engine 2000 Suzuki Vitara 1.6 8V, many mods 2004 Suzuki Ignis 1.5VVT 4Grip 2006 Suzuki Jimny 1.3VVT JLX+ and many more.
