Hello,
It is always beter to warm up these fuel injected engines, and possibly most other engines by driving the car at moderate rpms until warm up is complete. Factory literature mentions that driving off at moderate speeds is best for the warm up cycle.
I can only guess at the exact physics of this reasoning.
I suspect that the enriched cold fuel mixture has much more tendancy to load up on the cold spark plugs. In addition these injection systems tend to "wear rich" as they age. The increased rpms and load from driving the car would tend to make combustion chamber temperatures higher sooner during warm up. The injection system will cylcle through a wider range with the inputs of load and rpms during a driving warm up. The "warm up device" will also be able to cycle through its normal range of movement.
Another added bonus is the other moving parts on the car , wheel seals, differential, transnmission, steering are lubricated if the car is driven off. Mechanisms stick, corrode and seals and gaskets like to dry out, shrink and crack from lack of use. Another major bonus is the benefits to the brake system by driving the car. Rotors are rubbed clean, the brake fluid is heated, dispelling moisture, the calipers are excersized and seals and cylinders are lubricated. The same is true for the hydraulic clutch system if standard transmission.
Driving the car on a nice dry winter day will burn off some moisture and contaminants collected in the engine oil during cold starts!
Storing the car with fresh oil will prevent sludge from settling in the oil pan during storage. This will also remove moisture and combustion contamination which otherwise would be eating away at your engine during winter storage!
The saying "garages kill" makes a lot of sense.
Joe Alexander
Blacklick, Ohio
