If you keep your engine on it's leash this won't happen. don't leave doors open if you can help it, and it wont get out & run away... It's really a simple concept any engine owner will tell you.
Diesels don't have throttles, Gasoline engines do. If a gasoline engine had its injectors get stuck open at idle or half throttle, it would probably stall (the AFM becomes too rich to burn). the only way a gasoline powered car could theoretically "runaway" is if the throttle became stuck open (doesn't matter if it is carbureted or fuel injected)
Sorry. When i meant fuel injection i meant ELECTRONIC fuel injection. --- Post updated --- Not quite. With an electronic fuel injection i think that when you leave the gas alone the car drops RPM and saves fuel by avoiding to inject fuel. Creating engine brake. On top of that, i THINK that if they combine this with the old carbed rev limiters, the engine will cut off the sparkplug power.
That is partially true, engine braking is caused by the vacuum in the throttle body, as the pistons are trying to suck in air and the throttle valve does not allow sufficient air to get sucked in, slowing the whole engine and effectively braking (Imagine covering a straw with your hand and trying to suck air through the other side, it becomes very difficult) This is why diesels can't engine brake without an exhaust valve, jake brake, or similar device, as they have no throttle valve (save for a few exceptions, *cough* Mercedes *cough*)
Diesels can still enginebrake. The throttle is linked to the injector. Therefore you can just have the engine produce less power until it starts to drop RPM.
I don't think you got what I was trying to explain. I'm not saying that the injectors are always wide open on gasoline engines, I am saying that if by some odd chance that the fuel injectors became stuck wide open and the throttle was closed, the engine would stall. The only way for a gasoline engine to theoretically runaway is if the throttle was stuck wide open (essentially full throttle, but the throttle wont close)
If you run a diesel with no engine braking mechanism it will not engine brake. Trucks are the best example, and you can feel it yourself in Euro Truck Simulator 2 actually. Turn off the engine brake and just coast in any gear, you will not see any drop in RPM or significant slowing down of the truck as the engine is running on its own inertia, even with no throttle input.
Correct, but what i meant is that modern cars detect the position of the gas pedal. They dont inject fuel based just on the throttle body but also on the pedal. At least that's electronic throttle i think. So runaway engines on modern cars require a failure of the throttle body, AND failure of enough injectors to keep the car running. Since if you keep a single injector stuck open the car is still gonna stall since it wont work in an injector alone. I doubt games can represent what i mean exactly. If you set the ECU of a diesel engine to not add fuel when you aren't using the gas its very likely that there will be a big amount of engine brake. That with the engine compression and all.
Sometimes a Diesel can run away just by simply having too much oil, bad piston rings or bad turbo seals, if it starts sucking in crank case oil it will start to run off of it. Just thought I'd put that out there... Don't ask how I know about the too much oil one... It was an 03 Vauxhall Combo. Sadly the engine did blow... Never heard of a carburated car having this kind of rev limiter, carburated bikes, yeah, never seen one on a car though. Carburated cars usually rev till valve float.
