1. Checks on the car.
A) Start the engine, press the clutch pedal and check the operation of the drive when changing gears.
b) The system is normal if the drive only works when the first and reverse gears are engaged.
2. Vacuum cut-off valve check (The valve is located behind the intake duct).
A) Measure the resistance of the valve winding (normal 38.5 - 44.5 ohms). If the resistance is infinite, replace the valve.
b) Check for continuity between valve terminals and body. If there is a winding short to the housing, replace the valve;
V) Blow into port E of the valve: air must come out of the filter.
G) Apply battery power to the valve terminals, blow into valve port E: air should come out of port F.
3. Checking the gear lever position switch (Located on the right side of the gearbox).
Check the absence of continuity between the switch terminals with the pusher pressed (corresponds to the inclusion of 1st gear). With a free pusher, there should be no conductivity.