3.2 Diagnostic Screen Layout

3.1. Adjustments Detail:

*Fuel T-Value Fuel table value *Fuel F-Value Final value after compensations *Throt. Rate Rate of change in MAP *Accel, Fast + for acceleration, - for deceleration Dwell Duty Cycle of Fuel Control Valve Solenoid, 0-100% *Oxy-Corr % of fuel adjustment due to the oxy sensor feedback *Oxy-Wait Count down timer before oxy feedback starts *On Time Comp. Fast Acting Choke, depletes with revolutions completed

* Anon-adjustable preprogrammed value. Typically used only for MCFAengineering analysis.

Added Information on frequently reference parameters:

Manifold Pressure: Engine manifold pressure (MAP) is an indicator of engine load. Higher loads result in numerically higher MAPvalue. At idle the Manifold Pressure should be 35-45 kPa. At high idle (2700RPM) with the transmission engaged, the MAPshould be 42-47 kPa. At torque converter stall (transmission engaged, brakes fully applied to prevent movement, and foot pedal fully depressed) the MAP should read about 80-100KPa for one to two seconds. If your readings are different than these, inspect the vacuum hose to be sure it is not disconnected from the ECU, the fitting on the throttle body, or damaged. There are two barbed fittings on the throttle body. The lower fitting provides the MAPsignal to the ECU. The upper fitting should be connected to the distributor. If the hoses are all connected correctly and do not appear damaged, check the ignition timing. Correct timing is 10°BTDC.

Engine Temp: This will vary with the temperature of the engine. If the diagnostic monitor displays either 0°or 127°C it may indicate the temperature sensor has been physically damaged, a electrical short circuit occurred, or the sensor has been disconnected.

Battery Volts: This is simply an indication of the Battery Voltage and will vary with the battery state of charge and alternator output. When the engine is not running it should be close to 12 Volts. When the engine is running and there is an output from the Alternator you should see approximately 13-15 Volts depending on the battery's condition.

Actuator Power: This is the voltage signal the ECU sends to the Throttle Body Governor to energize the coils that controls the valve. At idle, it will read approximately 20-30 units, increasing with higher RPMs. At maximum load the output will be about 170-220 Units (Converter Stall Condition). NOTE: These val-

ues can vary significantly, but can be used to compare from one running condition to another and this trend of voltage change versus engine RPM and load can help during troubleshooting.

Dwell: This value is the amount of time the Fuel Control Solenoid Valve (FCSV) is activated and open to vacuum, by the ECU. The FCSV operates at specific "DWELL" based on fuel requirements. A50% dwell means the valve is open 50% of the time and closed 50% of the time. ADWELLof 100% indicates that the valve is open 100% of the time and the fuel control system is at full "lean". ADWELL of 0% indicates that the valve is closed 100% of the time and the fuel control system is full "rich".