Motor vehicles equipped with compression ignition (diesel) engines ... (c) Test procedure:
1. Visual inspection of the relevant parts of the motor vehicle's emission system to check that there are no leaks.
2. Engine, and any turbocharger fitted, to be at idle before the start of each free acceleration cycle. For heavy-duty diesels, this means waiting for at least 10 seconds after the release of the throttle.
3. To initiate each free acceleration cycle, the throttle pedal must be fully depressed quickly and continuously (in less than one second) but not violently, so as to obtain maximum delivery from the injection pump.
