Hi Bob,Brisbane (Australia is lovly as i visited in 2000).
You are probably right. It was differcult to make it idle when hot,so i had to adjust it with the flap.!! No good of course.
The WRD is working as intented,but with the setting were the fresh air filter and the air supply hose were interchanged i had to adjust the air intake flap to make it run at warm idle .This is of course not recommended as the flap shall be totally closed when idle.
It also affected the oil level in the pump as i think (but can not be sure) that the misplaced extra air hose created underpressure in the pump as it is connected to the intake manifold, this because that the WRD shuts of the air hose connector but probably leaves the fresh air filter open.
The oil level was increasing at a quick rate i had to suck out maybe a half a litre every 100 km. That concerned my so much if that something was wrong with the inj. pump.I visited a Bosch dealer but they found nothing.
Anyhow this all sorted out when the hose and the filter was put back to the correct spot. Smooth and robust idle and no significant change in oil level at the inj. pump.
Regards 91lux