I have heard this a few times.
On average (across all types of cars petrol or diesel) you use 0.45 litres of fuel to get an engine going when starting it up cold.

 

Probably yes, assuming it means until it reaches operating temperature, remember the AFR is lower (Richer mixture) on a cold start, not to mention everything is tighter.

Martin

 

Cool thanks for that .
I ment once you have let go of the ign key once it's fired up. Cause I notice my fuel gauge move a little downwards once I have started my car up lol. Cause I seem to be using less fuel doing a twenty mile trip to work going the long way round to Torpoint from Plymouth than starting and stopping my car whilst queuing and getting on and off for the ferry over to torpoint in Cornwall. Weird ????.

 

Older cars on cold start, probably. Seems a lot thou.

Newer cars with start/stop tech, definately not! Would make the function totally pointless.

 

Not a chance. 0.45 litres is roughly 0.1 gallons. The average 1.8-2.2 litre diesel uses 0.1 gallons per hour at idle. Using an hours worth of fuel in 2 crank revolutions is daft.

Also (geek warning, sorry I have powertrain development qualifications) a 1600cc Sigma petrol (1.6 zetec s, focus, mondeo etc) has a compressed chamber volume of about 35cc. 450cc of petrol in 2 revs (1 engine cycle) is 112.5cc of fuel per cylinder, it would lock solid. And diesels have compressed volumes of as low as 10cc in some cases. Sorry nerd off over.

Long story short, duff statistic mate

 

The actual figure is most likely out, but it is certainly true that a cold start uses more fuel, but no it won't affect the fuel gauge lol, that will be the shonky instrumentation!

Martin

 

Shonky instrumentation sounds a good reason.
cheeRS

 

As said, slightly higher consumption on start up but nothing that would show on the gauge. I expect the reading is going down because the battery voltage is being dragged down by the starter motor.

 

yes cars use a fair amount of fuel on cranking and priming pulse, but they only use around 3 times the idling values till started then use around 15-20% (depending on map) more gradually reducing till up to temp around 70-80 degrees.