Injector timing.html

Definition:

Injector timing is the delay before each injector output is fired.

Platform:ALL MAF based vehicles

Min Value:0


Max Value:720 Degrees


Description:

The delay is taken from TDC of the reference PIP signal for each injector output. The units for injector timing are absolute engine crank degrees. The range is 0 degrees TDC to 720 degrees TDC with 4 degree resolution. Either edge (on or off) of the injector pulse can be timed. The calibration switch INJREF defines the reference edge for injector timing. INJREF = 0, Use start of fuel pulse. INJREF = 1, Use end of fuel pulse. Regardless of which edge is used, the injector delay is used only to start a fuel pulse. Once started, pulsewidth accuracy has top priority. When the system is not in sync ( SYNFLG = 0), the injector timing is coincident with the relevant PIP signal. The injector outputs are fired in sequence after receiving the rising edge of the reference PIP signals. Actual timing will be the result of the random link between signature PIP (cylinder #1) and #1 injector output. When the system is in sync (SYNFLG = 1)
Hints:

The change in injector timing between consecutive injector firings is limited to a maximum of 45 degrees. This has the effect of walking the injector timing for large timing changes. 2. The final value of injector delay is limited to the range 0 degrees to 720 degrees. Intermediate calculations and results are maintained in an unlimited fashion. 3. The user must set DEGPIP to match his engine. DEGPIP is the number of engine crank degrees per PIP interval. (90 for 8-cylinder, 120 for 6-cylinder, 180 for 4-cylinder) See Also:
Scaling spark table RPM
Scaling spark table load