May 2005
Carburetion and Turbo Systems Inc.
Cars Trucks Busses and Locomotives LNG
FSA-1000 Fuel System Analyzer

The FSA-1000 Fuel System Analyzer is used to set-up and diagnose IMPCO closed-loop fuel systems.  The FSA- I 000 allows the user to view the oxygen sensor and the fuel control valve data simultaneously.  This makes finding problems with the fuel system simpler and faster.  The FSA-1000 comes with two cable assemblies to connect to various IMPCO control systems, as well as other brands.  It's operation and installation is described below.  For further understanding of the closed-loop system, see the IMPCO Principles of Operation booklet.

Operation

1. The MIXTURE LIGHTS indicate the air/fuel mixture by showing the actual oxygen sensor signal being received by the controller (computer). The lights indicate an air/fuel mixture that is rich or lean.  Green is LEAN and red is RICH.  They also show how fast the mixture is changing.  The lights are very useful in determing if the oxygen sensor is operating properly.

2. The DUTY CYCLE window displays the commands being sent by the controller to the fuel control valve (FCV).  These readings will be from a duty cycle range of 0-99.  A low reading (0-10) indicates that the controller is trying to achieve a richer mixture (fuel system too lean).  A high reading (90-99) indicates that the controller is trying to achieve a lean mixture (fuel system too rich).  A properly adjusted system wi 'II operate between 10-90 and constantly varying.
 

Connecting the FSA-1000

1 . Select the correct cable required for the system being tested.  The cable with alligator clips is used for conventional systems.  The cable with the 6-way connector is for COMMANDER I and COMMANDER 11 systems.

2. Ensure that the engine is not running and the key is in the OFF position.

3. Make connections with alligator clips:
 
 

A. BLACK wire to the negative (-) battery terminal.

B . RED wire to the positive (+) battery terminal.

C YELLOW wire to the YELLOW wire of the FCV, or to control wire of the FCV The control wire is the one that does not have 12 volts supplied to it.  This can be checked with a voltmeter when the FCV valve is disconnected.  The pin at the tip of the alligator clip should pierce the insulation.

D. GREEN wire of the oxygen sensor.  The pin at the tip of the alligator clip should pierce the wire.  Do not connect to the sensor side of the connector.  The sensor wire has a special Teflon insulation.  When proper connection is made, one of the lamps of FSA should light up.

With 6-way plug in cable:

1. Disconnect the 6-way connector from the COMMANDER.
2. Connect the jumper harness in between the COMMANDER and the engine harness.

Note: The FSA lamps will not illuminate until the key is turned on or the engine is started.  Power to'the FSA comes from the same power source as the controller. 

Adjusting Fuel Mixture (Highway Vehicles)

With the FSA connected to the vehicles fuel system, start engine and allow to reach operation temperature.

Adjusting The Idle Mixture

Ensure that the idle speed is set to manufac- tures speci ications.  Adjust the idle m ixture if screw while watching the oxygen sensor lights.  If the RICH lights are on, adjust the screw toward. lean until the LEAN lights come on.  Then turn the screw back until the RICH lights come on.  If the LEAN lights are on, adjust the screw toward rich until the RICH lights come on.  Then turn the screw back until the LEAN lights come on.  The mixer should then cycle between the RICH and LEAN lights.  At the same time, the duty cycle window should be between 30 and 70.  Rev engine slightly and return to idle.  Allow engine to stabilize for about one minute.  Readjust mixtures if necessary to obtain a 30-70 duty cycle.

Adjusting The Wide Open Throttle

Adjusting the wide-open throttle (WOT) mixture without a dyno and CO meter requires a location where you can safely perform WOT road test.  WOT test can be very short in duration since the FSA reads in milliseconds.  At WOT watch the oxygen sensor lights.  Just as with the idle adjustment, if mixture is RICH, adjust leaner.  If mixture is LEAN adjust rich.  The mixer should then cycle between the RICH and LEAN lights.  The duty cycle window should be between 30 and 70.  Return to idle speed and recheck mixture, occasionally the WOT setting wi 'II effect the idle setting.  Readjust mixturts if necessary.

Adjusting Fuel Mixture (Industrial)

With the FSA connected to the vehicles fuel system, start engine and allow to reach operation temperature.

Adjusting The Idle Mixture

Ensure that the idle speed is set to manufactures specifications.  Adjust the idle mixture screw while watching the oxygen sensor lights.  If the RICH lights are on, adjust the screw toward lean until the LEAN lights come on.  Then turn the screw back until the RICH lights come on.  If the LEAN lights are on, adjust the screw toward rich until the RICH lights come on.  Then turn the screw back until the LEAN lights come on.  The mixer should then cycle between the RICH and LEAN lights.  At the same time, the duty cycle window should be between 30 and 70.  Rev engine slightly and return to idle.  Allow engine to stabilize for about one minute.  Readjust mixtures if necessary.

Adjusting The Wide Open Throttle

Adjusting the wide-open throttle (WOT) mixture requires loading the engine.  This can be accomplished by using the forklifts hydraulic system.  WOT test can be very short in duration since the FSA reads in milliseconds.  Do not operate at full load for more than necessary to obtain a reading.  Allow vehicle to cool if hydraulic tank becomes hot to the touch.  Tilt back on the forks at WOT to apply a load while watching the oxygen sensor lights.  Just as with the idle adjustment, if mixture is RICH, adjust leaner.  If mixture is LEAN adjust rich.  The mixer should then cycle between the RICH and LEAN lights.  The duty cycle window should be between 30 and 70.  Return to idle speed and recheck mixture, occasionally the WOT setting will effect the idle mixture setting.  Readjust mixtures if necessary to obtain a 30-70 duty cycle. 

 
Troubleshooting Guide
Mixture lights:
                     Switching between RICH and LEAN.
Duty Cycle: 
                     Varying between 30 and 70
System Working Normally
Mixture lights: 
                 Only RICH are lights on.
Duty Cycle: 
                 Duty cycle fixed below 50.
Mixture is RICH although the controller is commanding a rich mixture.  Controller is responding incorrectly.
Check for:
*Vehicle is not yet operating in closed loop.  Allow running for a few more minutes.
*Sensor, wiring or controller problem.
 
 
 
Mixture lights:
                     Only LEAN lights on. Duty Cycle:
Duty cycle 
                     fixed above 90
Mixture is lean because controller is commanding a lean mixture.
*Check for a problem in the sensors, controller or wiring.
Mixture lights:
             Only RICH are lights on.
Duty Cycle:
              Duty cycle fixed above 90.
Mixture is RICH although the controller is commanding a lean mixture.
Check for:
*Very dirty air filter restricting airflow.
*Carburetor problem preventing a lean mixture.
 *Incorrect air/gas valve assembly.
 *Worn carburetor body.
Mixture lights:
                    Only LEAN lights on.
Duty Cycle:
                    Duty cycle fixed below 50.
Mixture is LEAN although the controller is commanding a rich mixture. Controller is responding correctly.
Check for:
* Manifold or vacuum line leak preventing a rich mixture.
* FCV sticking not allowing vacuum to converter to shut off.
* Faulty oxygen sensor.
* A faulty spark plug.
* A faulty spark plug wire.
IMPCO TECHNOLOGIES, INC.
16804 GRIDLEY PLACE
CERRITOS, CA 90703
Phone: 562.860.6666
http://www.impcotechnologies.com