Page 10
IF THE ROTATIONAL BARREL IS IN THE FULLY OPEN POSITION the problem lies with the
mechanical gas system, not the FP50. Areas to examine would be: A/ the correct mixer is fitted to
the vehicle, B/ no air leaks exist in the vehicle’s intake system, especially around the mixer, C/ the
inner wall of the vapour hose has not collapsed nor is the hose kinked, D/ the convertor is
delivering gas without fault, E/ the tank contains a useable amount of gas, F/ the excess flow valve
(in the tank) has not triggered, G/ the filters in the gas solenoids are not blocked.
IF THE BARREL IS NOT IN THE FULLY OPEN POSITION the problem is likely to be a wiring
fault, or the processor, or valve itself. Check the following: A/ the fuel processor is
earthed to the
negative side of the vehicle’s battery
and not the vehicle’s chassis, B/ the loom connector to the
CV30/CE30 is fully plugged in. If the above have been checked carefully, replace the CV30/CE30
stepper valve and retest. If the problem remains, replace the FP50 (the original CV30/CE30
stepper valve may well be fully operational).
FP50 RICH LIGHT IS ON ALL THE TIME
Ensure that the CV30/CE30 stepper valve is plugged into the FP50 and the stepper loom is
undamaged.
Check that the FP50 is
earthed to the negative side of the vehicle’s battery
and not the
vehicle’s chassis. Ensure that the FP50’s oxygen sensor wire is not connected to the oxygen
sensor heater wire. This will give a constant rich reading while the oxygen sensor is being
electrically heated. On some vehicles the heater wire will c12 volts for several minutes. If
the heater is turned off when the sensor is hot, the FP50 will then read a constant lean signal from
this time on.
If the green ACCEL TPS SET light is
constantly on
, the CV30/CE30 valve will be held open. If the
green ACCEL light is
constantly on
, check that you have the correct TPS output wire. You may
have connected the green TPS input wire to the TPS earth wire or to a throttle position
switch
(which does not give a slowly changing voltage on acceleration). For the standard FP50, the
minimum TPS voltage (at idle) is 0.20 volts and the maximum TPS voltage (with the accelerator
fully depressed) is 5.0 volts. TPS sensors wear with age and if the voltage increase is not even the
sensor may need replacing.
NOTE:
1/ For the FP50-DS-SS, the green ACCEL light will flash at approx twice per second when the
throttle is held below the TPS/RPM SET potentiometer setting. The flashing green ACCEL light
indicates that Open Loop has been selected. This will cause the valve to remain open. Open
Loop operation should only occur at idle.
2/ For models FP50-DC & FP50AC the green ACCEL light will flash at approx twice per second
when the throttle is held below the petrol to gas changeover point (the vehicle is therefore
prevented from changing over to gas). This does however not cause the CV30/CE30 stepper
valve to remain open.
Finally, check the CV30/CE30 stepper valve. At revs ensure you can lean the mixture by screwing
in the power valve. If you need to turn the CV30/CE30 power valve inwards by more than 2 turns,
return to step 6. and retune the vehicle.
If the orange Rich light remains on, check that the CV30/CE30 is actually fully closed. Run the
vehicle on gas at 1500 rpm for 15 seconds. Immediately stop the engine by
turning off the
ignition.
Unscrew the manual power valve on the CV30 stepper valve. If the rotational barrel is
Summary of Contents for FP50 Series
Page 2: ......
