Driving & Driving Test Tips: Engine warmup method, road traffic law, friends and neighbors

Question
My friends and neighbors all seem to let their cars idle for a minute or two (or more!) when the engine is cold. But with gasoline costing more than $2 a gallon, that seems like a waste to me. I say it does no harm to drive off as soon as the car starts. Who is right?

Answer
Dear Patrick,

I am not really the correct person to be asking this question, you really need to ask a vehicle mantainance expert. I am more of an expert on driving and road traffic law (in the UK)

As far as I am aware there could be some advantage to leaving your engine running for a minute. Most engine damage occurs in the first few minutes after switching the engine on, as the oil tends to leave the moving surfaces while the vehicle is switched off. If you increase the engine revs before the oil has had chance to recoat the moving parts of the engine you may do more damage. Also some turbo charges may be damaged if you don't leave the engine at idle after you switch on the engine.

Like I said, This is not really my subject so you should consider asking another expert before relying on my advice.

As for the cost of fuel. Here in the UK the current cost of fuel is 85 pence per litre ($7.50 a gallon) so it could be a lot worse.

Sorry I couldn't have been any more help, If you have any more questions don't be afraid to ask.

Yours.


Paul