Converting negative reported timing advance to
Application: GM V6 based vehicles
For many late model GM V6 based vehicles (those derived from the
3800 Series II platform) the factory computer will report positive
timing as a negative number.
VCM Suite 2 allows two solutions to this:
Create a user defined PID and insert into the table as follows:
How it works: The scanner will average the values of all sensors of
same type currently being scanned. What we have done here is create
a new PID that returns 3x the spark advance in the positive
direction so that when it averages the two values you get the
actual spark advance in the positive. You shouldn't have to change
your histograms, charts, gauges etc. as they all log as sensor
based by default.
- Name: Timing Advance - V6 Fix
- Abbrv: Adv - V6
- Sensor: Timing Advance
- Units: °
- Function: -3.0 * [PID.14]
This method is similar but uses -1.0 * [PID.14] as the function.
You would then have to go switch your histo's and charts etc. to
plot the PID value rather than the sensor value.