400E (124.034) V8-4.2L (119.975) (1992)
and below a specified air mass. The air is injected for a maximum of 110 seconds depending on coolant temperature. The oxygen sensor control in
inactive during air injection.
Camshaft Timing Control
To improve the torque characteristics of the engine, the intake camshafts are "advanced" depending on engine speed and load.
The LH control unit operates the camshaft timing adjuster solenoids (one per camshaft). When the solenoids are energized, the camshafts advance. In
"P" or "N" the adjustment is dependent on engine RPM only.
Engine speed:
Adjustment:
Up to 2000 RPM
Retarded
From 2000 - 4200 RPM
Advanced
From 4200 RPM
Retarded
Above 250 km/h (155 mph)
Advanced
Selector in "P" or "N"
up to 3000 RPM
Retarded
Selector in "P" or "N"
from 3000 RPM
Advanced
Charcoal Canister Purging Control (EVAP)
The fuel vapors stored in the charcoal canister are purged at temperatures above 70 °C (158 °F) via the purge switch-over valve (Y58/1). The vapors
then get burned in the combustion process. In order to control the purge quantity, the LH control unit activates the switch-over valve at a frequency of
7.5 Hz (cycles). The purge quantity is determined by the duration of each cycle.
Exhaust Gas Recirculation Control (EGR)
The EGR valve is controlled by the LH control unit via the EGR switch-over valve (Y27). This switch-over valve is activated at coolant temperatures
above 65 °C (149 °F) and only if the engine is between the idle and full load condition.
Transmission 1>2>3 Upshift Delay Control