Fuel Injection Systems – How do they work?

[Kaz]

I got my first car in 1976, and the car was older than that. When I first started doing DIY on my car, we had “tune ups”, and you had to gap points, distributor wires or caps that would crack or gain moisture, and you had carburetors. Hell, I had a very cool INDUCTIVE timing light! You had to know how many degrees before TDC your car should be to adjust the distributor.

Later on in life, I stopped doing my own automobile repair and when they came out with Electronic Fuel Injection, it was really a black box to me. Now that I’ve put my old tools back into service by doing my own repairs, Eric’s most recent video on rebuilding a carburetor (which was great) has inspired me to ask: “what about EFI?”

With that in mind, I wanted to suggest/ask if Eric would mind doing a video on how EFI works, how to diagnose certain issues, etc. That rail scares me – what the heck is that thing? When do injectors go bad? How do you replace them? What should we listen for?

Maybe he’s done a video on it, but I searched the suggestion forum and couldn’t find anything related; and maybe this isn’t the place to ask for a video about this – if that’s the case my apologies.

Here’s what I know: if Eric does a video on something he’s pretty thorough, informative, and uses clear and concise language. So if there were an EFI video, I’m sure I would learn a lot, and maybe even head off issues before they become issues, ya know?

Thanks for your time.

Topic

[EricTheCarGuy]

Thanks for your suggestion. I have tried to cover some of the specific systems in EFI but haven’t made a video on the overall functions of it. There’s a lot to cover with that topic however and it might be some time before I’m able to come up with a script for one. I’ll certainly keep it in mind however.

Thanks again.

[Bryan Carter]

Yeah I think this would a tough video to make.

The very basics of fuel injection are fairly straightforward and can be easily understood by anyone with a decent working knowledge of engines. Unfortunately the basics won’t help anyone diagnose problems. To do that, you have to get more advanced, which would get ugly and cumbersome with rapidity.

Not to mention it’d leave the door wide open to the hordes of your more pedantic internet experts. “But Eric…” they’d whine “that’s only true for peak-hold injectors, not the saturated or disc types. Also at 11 minutes you were talking about the fuel return line, which doesn’t apply for returnless systems. Also your explanation of MAP vs MAF air metering didn’t take into account…” ad nauseam.

So Eric would have the unenviable task of pleasing the nerds (which can’t be done) without leaving everyone else cross-eyed. No simple feat. But I’d definitely watch whatever he whipped up.

[Author]

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