10
SENSOR VERIFICATION
Before starting the vehicle, verify that all of the sensors are reading properly. To do this, turn the key off, and cycle it back on.
You should hear the fuel pump come on and run for 5 seconds.
Note: This is a great time to check for fuel leaks!
On the HOME SCREEN, select the MONITOR icon, then select the “Monitors” screen. You will see an icon named “Initial
Startup”. Select this. With the key on and the engine off, these sensors should read as follows:
Engine RPM
– This gauge should show “Stall!”, once you begin cranking the engine it will show actual engine RPM
TPS
(Throttle Position Sensor)
– Should read 0. Slowly depress the throttle to wide open. It should read between 85
and 100% at wide open throttle. If it does not, please verify your throttle linkage is allowing full travel of the throttle arm.
MAP
(Manifold Air Pressure Sensor)
– Should read from 95-102. At high elevations it could read as low as 75.
CTS
(Coolant Temperature Sensor)
– reads engine temperature.
IAC Position
–
See Idle Setting/Throttle Plate Setting section in this manual.
Battery
– Will read battery voltage. Should be 12.0 volts minimum.
If ANY of these sensors are not reading properly, it must be resolved before the engine is started.
STARTUP
With the handhel
d still on the “Initial Startup” screen, crank the engine and look at the RPM parameter. It should change to
“Syncng”, indicating the ECU is syncing with the RPM signal for an instant, then show an RPM signal. The engine should fire
and run and come to an idle.
If you do not get an RPM signal, there is an error in the wiring or system setup. Call Holley Tech service for advice.
If the engine starts but is idling too low and appears to be struggling for air, you may have to open the throttle body idle speed
screw at this time.
AFTER-STARTUP
Once the vehicle has started, look for any fuel or coolant leaks. Let the vehicle warm up and look at some other parameters to
make ever
ything is operating properly. Go into the MONITOR, MULTI GAUGE, and select the “AIR/FUEL RATIO” Icon.
Closed Loop Status
–
Indicates whether the engine is “Closed Loop” or “Open Loop”. Closed Loop indicates that the
ECU is adding or subtracting fuel to maintain the target air/fuel ratio. The Sniper EFI calibrations are such that the
system should be operating closed loop almost all of the time.
CL Comp
–
This is the percentage of fuel that the ECU is adding or subtracting to maintain the target air/fuel ratio at
any specific moment. A value with a minus (-) sign in front indicates the ECU is removing fuel. A value with no minus
sign indicates the ECU is adding fuel. When in open loop operation, this will always stay at 0%.
Target Air/Fuel Ratio
–
This is the target AFR (air/fuel ratio) the ECU is trying to maintain. This will vary depending on
the engine speed and load.
AFR, A/F
–
This will show the air/fuel ratio the wideband oxygen sensor is reading. The Closed Loop Compensation
should be adding or subtracting fuel all the time such that the AFR Left should always be close to the Target AFR
value.
Fuel Learn Status
–
This indicates the status of the Sniper EFI “Self Tuning” operation (Learn Status). The system
will automatically tune itself as you drive around. There are several conditions that must occur in order for the Self
Tuning to occur. The engine temperature must exceed 160° F. The system must be operating in a closed loop mode,
and the Self Tuning must be enabled. The base Sniper EFI setups have the Self Tuning enabled. Once the engine
reaches 160°
F, the Self Tuning should be active. The Learn Stat will show “NoLearn” when Self Tuning is not active
and “Learn” if Self-tuning is active.
If any of these parameters are not showing a proper value, find out why before further driving the vehicle.
Fuel Prime occurs 2.5 seconds after key-on (which is also the amount of time it takes for the
3.5” touch screen to load). If you quickly turn the ignition key without waiting for the full 2.5
seconds, the prime will not occur and it may take longer for the engine to start.
Caution! Multiple key cycles without firing the engine could potentially cause a flooded condition
Содержание Sniper EFI 550-510
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