We all saw Mason’s Viggen engine all mashed up and golden brown like a nice toasted ham and cheese sandwich, now it’s time to get a little more learned about how a nice lean one looks and works.

Specifically, we’re talking about how fuel gets into a Saab 284L engine, the V6 in the Saab V6 Aero. TedJS is a GM World Class Technician and professorial type at Tri-C – a community college in Ohio. He was preparing a lecture on fuel injection when he saw Mason’s post yesterday and decided to send these through.

Apologies for the brief comments only, but these were done on the fly:

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Upper intake removed:

There is the fuel rail – check out the heat reflective tape that is around some of the injectors and connectors.

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Close-up of injector going into intake port

Lower injector o-ring provides seal against vacuum leaks:

There is the fuel rail fully removed from the intake:

And taken apart (you are looking at a removed injector and the fuel rail pressure sensor). The pressure sensor is used as an input to the computer to control the variable speed pump.

Here is the injector:

Fuel leaves the injector and is atomized here (broken down into really small parts so it vaporizes)

So where does it go? Right here: the lower intake manifold (containing the injectors) is now removed (those are some monster intake ports!)

Same view with gasket gone:

Close-up of the intake valves – this is where the fuel is sprayed into the cylinder. When the valves are hot they help keep the fuel in a vapor form:

Upper intake removed from engine (you can see the injector ports and intake ports):