AEM 30-6905 Universal Programmable EMS-4 - Manual (Page 122)

Page 122 of 279 EMS-4 Install and Tuning Guide_Rev 1.6
12V Power
Chassis Ground
0-5V Output
Serial Output
BOSCH LSU4.2 UEGO Sensor
Controller
UEGO
Gauge &
RED:
BLACK:
WHITE:
BLUE:
The following is a chart of typical AFRs. Note that every engine is different and this may not
be the optimum set up for your particular vehicle. The AFRs on this chart are very
conservative to minimize the potential for engine damage. These AFRs depend on the
condition that ignition timing and fuel octane are adequate enough to prevent knocking. The
very low loads found in the lower right corner occur during deceleration, and because there is
no “work” being done by the engine, AFRs during deceleration can be very lean. We have seen
AFRs of 20.0:1 during deceleration runs.