Table of contents: Six-cylinder engine ↓ Functioning ↓ Disruptions in work ↓ Checking the air preheating ↓
Six-cylinder engine
The automatic preheating device for intake air is located on the inlet side of the air filter housing. Its task is to maintain a favorable temperature of the air sucked in by the engine.
There is a reason for this: in cold weather, the fuel-air mixture is more saturated if the intake air is supplied preheated. The same amount of warm air takes up more space than cold air. Since the engine can only suck in a certain amount of air, when the preheating is on, slightly less air is supplied - the mixture becomes richer, fuel consumption increases. For smooth engine operation, this is only necessary at low temperatures.
Functioning
The intake air preheating flap is controlled by a thermostat, which fully opens the supply of warm air at a temperature of -20°C. As the temperature increases, the flap slowly closes until it closes completely at a temperature of +5°C.
Disruptions in work
If the air preheating does not function satisfactorily, this may lead to operational problems.
In the cold season:
- Unstable idle speed after starting a cold engine during the warm-up stage.
- Poor shifting, engine prone to misfires.
In the warm season:
- Reduced power, maximum speed not reached.
- Increased fuel consumption.
Checking the air preheating
Six-cylinder engine
1. Remove the filter insert.
2. Look into the hose pipe, use a flashlight if necessary.
3. Depending on the ambient temperature, the air damper should close the supply of cold or warm air.