On the 2014 Honda Civic why is it necessary to let the engine idle until the blue “C” light icon goes off? I wish the dealership had given me this information when I bought the car. It was not until a couple days later that I called the dealership about it.
Why does the engine use synthetic oil?
And, where can I get info on what all those icons stand for on the dashboard?
The engine uses synthetic because it calls for a 0W-20 weight oil and that only comes in synthetic. I am not sure what the C light is but it should be in your owner’s manual.
We have sent a lot of owners to that manual but on reading through a few of mine, I notice that some of them are pretty outdated and refer to a few models older cars.
I also seriously doubt that driving off with the C light on would cause any harm to the car. That is despite not knowing what that light is.
You can view the owners manual online until your owners manual arrives.
http://owners.honda.com/vehicles/warranty
The cold engine light does not prohibit movement, it is an indicator to advise against racing the engine. The owners manual advises that if the cold light remains lit for longer that normal the vehicle may have a problem. You should not idle the engine until the light goes out.
As mentioned, just drive off but don’t race the engine. My Mazda works the same way; it does not have a temperature gage and the blue light goes off after I’m underway.
If the blue light stays on you have a problem.
Nevada_545: I don’t have one but I guessed a “Blue C” could mean cold. Could there be hope for me diagnosing vehicles newer than 1976?
It’s in the owner’s manual. The “C” accompanies a thermometer icon. It means that the engine is cold. I think you can drive with a cold engine, but drive gently until the light goes out.
Like my chemistry teacher used to say “It’s in the boooook son”. We called him Black Bart because he had silver nitrate stains all over his hands. One day he just disappeared behind the counter for a few minutes. We weren’t sure what to do but then he appeared again after some kidney stone pain, I guess. Nice old guy though.
Its been fun today but I’ve got to work on taxes.
I agree with the others here; give it a few moments to get the oil circulated and then drive conservatively and the engine will be fine.
The exceptions are in very cold weather where you either have to use your defroster or you need to warm where your buns sit. The defroster is a safety issue. It won’t work until the engine gets a bit of heat in it. The buns is from experience in North Dakota. You haven’t known discomfort until you’ve jumped your buns onto frozen-solid foam a sub zero temperatures. You’ll want to prewarm the car a bit ever after. 
It’s all in the owner’s manual along with other useful information. There are quite a lot of icons in Hondas nowadays, so it’s a good idea to keep the manual in your car in case one of them lights up.
As the others above say, I don’t think the intent of the C is to prevent you from driving away, but just to inform you the engine coolant is still on the cool side. When the coolant isn’t up to normal temperature the engine computer uses a different algorithm so the fuel mixture is richer than normal. If you really gun the engine in that condition you might risk forcing some raw gasoline vapors past the rings and into the engine oil, which is undesirable for a long engine lifetime.
The engine uses synthetic oil because Honda wanted the car to get good mpg numbers. mpg is an important factor that buyers consider, so it affects car sales. Synthetic oils can be made thinner and slicker and still deliver the needed protection, so friction losses are reduced and mpg is enhanced. Many newer cars require low viscosity synthetic oils these days. Suggest you follow Honda’s advice regarding the oil, as your engine probably uses variable valve timing, which is highly susceptible to expensive problems if using the wrong oil or wrong oil viscosity.