That's basically it, Shrew.
FI delivery systems need fuel pressure at the injectors to operate, some of them quite high fuel pressure, whereas carb'd systems need virtually none. In a nutshell, carb's rely on a device called an accelerator pump to squirt gas into the throttle bores of the carb which then, along with air, gets sucked into the manifold and cylinders. Then, once the engine is running, air flow through the carb throttle bores actually draws gas from the idle, transition, and primary circuits to keep the engine running, and the accelerator pump squirt then serves to enrichen the "lean" (too much air) condition created when the throttle is initially opened.
So, when the engine is first started, especially when it is cold, "pumping" the throttle of a carb'd engine serves two purposes; 1) it sets the fast idle and/or choke and 2) it makes the accelerator pump squirt some gas to help a cold engine start. You're not priming the carb - there is probably already fuel in the carb, you're really priming the cylinders. A fully warmed up carb engine shouldn't need to have the throttle pumped. In other words, if the engine is running and fully warmed up you should be able to turn it off, let it sit for 1, 2, 10, or 15 minutes and then restart it without fussing with the throttle at all.
FI doesn't need any of that, the computer takes care of it. So like Shrew mentioned, turn the key to the "On" position before trying to start the engine. You may be able to hear the electric fuel pump run to build up the required pressure for the injectors. Note, however, that it really only takes a matter of seconds for the pump to build pressure. By the time the pre-start alarms stop sounding there will be enough pressure to get the engine to start.
Dan
|
Linear Mode
