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The last post is correct, you do not need to post-idle your engine, and I am saying this as an engineer for a turbocharger company. On a water-cooled center-housing turbo (all modern gasoline turbos), the cooolant continues to circulate a bit even (thermo-siphoning) after the engine shuts down...

You might as well ask Does Power matter. Vehicle performance is proportional to Power /Weight ratio at all speeds below the point where aero drag gets dominant. To be more specific, vehicle acceleration is proportional to the Power delivered to the wheels / (vehicle mass x vehicle speed). So...

The modern AT is actually not more efficient than a modern manual gearbox. Even the best AT's have additional friction and pump loads. It is just that this is overcome by the additional gear ratios, usually allowing a much more efficient overall top gear ratio. Another big factor is that the...

Whether you are idling or actually driving a cold engine, a modern Direct-Injected engine only runs rich during cranking and the first few seconds of running. Ask any engineer who has actually calibrated a modern passenger car engine. Dave

Yes they do! Dave

On a cold winter day, using a remote starter is the worst way to warm up an engine that you care about. You maximixe the amount of water and fuel you introduce to the crankcase and waste gas. Just get in and drive, taking it easy until the engine is fully up to temp. Dave

When you start your car and just let it idle, you are doing the equivalent of adding a few tablespoons of water to your crankcase. During idle, especially from a cold-start, you introduce water vapor to the crankcase because every piston on every engine cycle leaks some combustion gas past the...

Not due to rich mixture, All gasoline engines produce a very small concentration of Soot even when runing the perfect air/fuel ratio. Even when running lean. GDI engines tend to be a little worse than PFI engines. The very small soot content eventually coats all of the surfaces it flows...

I have personally seen these kind of tests numerous times (I am an engine engineer) and can assure you that even the worst engine gets all of the bearings pressurized oil within 5 seconds from cold-start. Dave

To be more accurate than saying performance is about Power/weight, I would have to say that performance is all about (area under the power curve between useable rev-limits) / weight Dave

I also wonder if the fuel meliage is really that much worse than the SI, and if so, why. Dave

I hate to get all technical on you all, but this is not true, unless by torque you mean torque at the axle, not at the engine. The transmission and final drive multiply torque; so you may feel you are "driving torque", but the only engine parameter that is directly proportinal to acceleration...

Realize that extended-idling is the worst way to warm-up an engine

Even the worst-designed engine gets pressurized oil to every bearing in the engine within 5 seconds of a cold-start. This is theoretically a concern, but for all practical purposes you don't have to worry about it; and you certainly do not have to wait more than 5 seconds from a cold-start to...

It is the Catalyst heating Mode. Passing Federal emissions standards is all about getting the substrate inside the catalytic converter "lit-off" as soon as possible. The combination of high rpm and retarded spark timing can get the cat over 200C in less than 15 seconds Dave

The technology (design, materials, manufacturing, tribology) of engine pistons, valvetrain, rings and bearings have progressed tremendously in the past few decades to the point where the parts that are most sensitive to the "break-in" period, the piston and ring assembly, are nearly bullet-proof...

Modern Catalytic Converters achieve light-off temperture in 15 - 20 seconds from cranking. Don't worry about your Cataltic converter.

Just a little factoid: Direct injection engines are not worse than PFI or carbureted engines on oil dilution issues with not getting the engine warmed-up. In fact a GDI engine actually uses and wastes less gas than a PFI engine on cold-start. The issue is that if you never get the oil in the...

A couple of thingsto note from an engine engineering POV: Just becaust the CRV version of the engine has this problem doesn't mean that other versions do. Simply changing the injector specification/design and/or the injection timing will have a dramatic effect on how much fuel sprays on...

As I have posted several times, the proper shift speed varies with how hard you want to accelerate and whether you are going uphill or downhill. There is no single correct set of shift speeds for all purposes. Dave