====== InjBatteryAdj ======

In the direct access area of ECMLink, there is a table called InjBatteryAdj.  This table is indexed by battery voltage and provides an appropriate deadtime adjustment at the corresponding voltage.  As voltage drops, injector response changes.  Less voltage results in a "slower" injector and the need for more deadtime.

This page provides a simple explanation of how to "see" the effect of this table in your datalogs.









===== Before adjustment =====

The picture below shows a clip of a datalog where the power window switch was used to raise the windows until the windows were closed and then the switch was held a few seconds longer to produce a load on the alternator.  As you can see, this dropped battery voltage and the mixture went lean as a result.

{{https://www.ecmtuning.com/images/forums/injbatadj-1.gif  }}

The following is the InjBatAdj table that was used.  The injectors in this case were FIC 850s running at 43.5psi base fuel pressure.

^    ^  Deadtime  ^
^  Voltage  ^  (usecs)  ^
|  7|  2490|
|  9|  1530|
|  12|  1215|
|  14|  1020|
|  16|  930|
|  19|  825|

**NOTE:** That list is total deadtime.  To use with ECMLink, set the deadtime offset field on the Fuel tab to zero.




===== After adjustment =====

Based on the data from above, the 12-volt entry was increased by 150usecs.  The 9-volt entry was also increased just to provide a "smoother" transition to the 7-volt entry.  The result is shown in the image below.

{{https://www.ecmtuning.com/images/forums/injbatadj-2.gif  }}

The following is the table that was used.

^    ^  Deadtime  ^
^  Voltage  ^  (usecs)  ^
|  7|  2490|
|  9|  1905|
|  12|  1365|
|  14|  1020|
|  16|  930|
|  19|  825|
**NOTE:** That list is total deadtime.  To use with ECMLink, set the deadtime offset field on the Fuel tab to zero.