1. Start the engine and warm it up to a temperature of 80-95°C.
2. Connect a tachometer.
3. Install a tee in the vacuum hose connecting the fuel pressure regulator and the air intake chamber, then connect a vacuum gauge to the tee.
4. Start the engine and leave it to idle. Make sure that the speed of the crankshaft corresponds to the required one and take readings from the pressure gauge (pic. 3.12).
Minimum value on the vacuum gauge: 60 kPa
Pic. 3.12. Checking the vacuum in the intake manifold with a vacuum gauge