If you watch old films, ( Bond etc) , whenever they arrive anywhere in a sports car, they always blip the throttle and immediately turn the engine off. My Dad used to do it years ago when he had an Alfa Spyder and a mate does it whenever he drives an old sports car.Dunno why?. Did it do anything usefull,or did it cause damage ( I've heard of unburnt fuel washing the bores clean of oil) .Anyone know why it was the thing to do,and does anyone do it with their Z?
Blipping the throttle when switching off
- Thread starter bigshurv
- Start date
Don't need to do it with the Z, I did though on my racing puma as if you didn't, when you went to start it it would turn over for a good few seconds before starting. That had a special inlet manifold along with advanced timing and other things, sure someone can give you a technical answer
CornishRob
Senior member
You shouldn't do it on anything with a Turbo or you will risk the turbo running unlubricated as the oil pressure will drop.
Just got this from "How Stuff Works" website...
Don't Rev the Engine Before Shutting Off the Ignition
Many of us learned to do this on carburetor-equipped engines in the belief that stomping the gas pedal as we turned off the switch would "prime" the carb (put a jolt of gasoline in its bowl). Most of the time, it did little or no good even for a carbureted engine.
For today's fuel-injected engines, it's a complete waste of fuel. Not only that, but the final spurt of gasoline also winds up dumped on the cylinder walls where it can wash away the essential lubricant, paving the way for increased wear.
I never did it , that's what a fuel pump is for... 8)
Don't Rev the Engine Before Shutting Off the Ignition
Many of us learned to do this on carburetor-equipped engines in the belief that stomping the gas pedal as we turned off the switch would "prime" the carb (put a jolt of gasoline in its bowl). Most of the time, it did little or no good even for a carbureted engine.
For today's fuel-injected engines, it's a complete waste of fuel. Not only that, but the final spurt of gasoline also winds up dumped on the cylinder walls where it can wash away the essential lubricant, paving the way for increased wear.
I never did it , that's what a fuel pump is for... 8)
Little good? Doesn't even make sense for carbureted engines. Those of you old enough to recall, 1st thing you do to start is to push the accelerator pedal to the floor once to set the choke, assuming automatic choke. This also pumps a good amount of liquid petrol into the carb throats via the accelerator pump. When really cold, you give it more pumps for more petrol for a very rich mixture.
A little blip when shutting down contributes nothing to a future start up in the throats and manifold. One, most of it is burned immediately. Two, any left will have evaporated by the time one returns to restart. And keeping the bowl full makes even less sense. Unless one's fuel pump is knackered, the bowl is almost always completely full. The float valve sees to that. When shutting down, the fuel pump is more than likely pushing against a closed valve. If anything, you're depleting the bowl a bit by pumping fuel out and shutting down before it has a chance to refill. I don't see there ever being enough liquid petrol to wash the cylinders, the engine is still running after all. That is simply way too rich. You would be getting more obvious problems than increased wear.
I stand by we did it because it sounds ace.
A little blip when shutting down contributes nothing to a future start up in the throats and manifold. One, most of it is burned immediately. Two, any left will have evaporated by the time one returns to restart. And keeping the bowl full makes even less sense. Unless one's fuel pump is knackered, the bowl is almost always completely full. The float valve sees to that. When shutting down, the fuel pump is more than likely pushing against a closed valve. If anything, you're depleting the bowl a bit by pumping fuel out and shutting down before it has a chance to refill. I don't see there ever being enough liquid petrol to wash the cylinders, the engine is still running after all. That is simply way too rich. You would be getting more obvious problems than increased wear.
I stand by we did it because it sounds ace.
It was supposed to prevent running on (pre-ignition self-detonation) in old carb equipped cars. If you've ever had a car run on you'll know what a weird and almost frightening situation it is to have shut down but find the engine still thumping and firing randomly as if it's about to fall to bits, but not be able to stop it. Left to it's own devices it sometimes led to a huge backfire through the carb 
...and blipping sounds good :lol:
...and blipping sounds good :lol:
I've driven a Fiat 126p, a Łada 2107, and a Hyundai Pony - maybe the possibility never occured to me at that time, but I never did it. But still, they were newer carburettor cars anyway.
corsaire77 said:
That's quite an Eastern Europe shed collection!
