Quote:
Originally Posted by MetroMPG
Didn't see this engine efficiency feature in the original article:
Source: https://www.greencarreports.com/news...on-2-cylinders
This, in combination with the electric water pump, can keep providing cabin heat in cold temperatures even when the engine auto-stop feature is active.
I know most conventional heaters will quickly run out of heat within a few seconds of stopping the engine, if the HVAC blower is still on. |
That's becoming more common in boosted gasoline engines. Also, the exhaust manifold is integral to the head and has a coolant passage. Not sure if GM is doing this, but in some cases the coolant loop to the head/exhaust manifold can be split off so that it is on a separate loop from the block. That allows priority cooling to the top of the engine to mitigate knock at high load without having to go deeper into command enrichment or spark retard. It also allows the exhaust to reject some heat to the cooling system to keep turbine temperatures lower at higher loads. During cold start, coolant flow is usually restricted to the head/exhaust manifold to aid with catalyst light-off.