OK, time to wake up this section. So you've got a stock older Porsche (or even Ford or some such) that isn't intended to be a Concours winner, but the engine room has been neglected for so long, appearance wise, that you keep it locked under the hood like a Victorian half-wit nephew that the family doesn't want anyone to see...and you really don't have a lot of time to spend detailing under the hood, right?
Well, here's a way to bring that nasty space back to a semblance of respectability, and to keep you from unconsciously looking over your shoulder in fear that the city's codes department will condemn your driveway as a slum, every time you raise the hood.
Go to your local auto parts store and pick up a spray bottle of whitewall tire cleaner, to serve as a non-flammable water-based degreaser. Also grab a bottle of your favorite NON-petroleum based (the petroleum based stuff tends to dry out plastics/vinyls over time--think wiring) protectant or tire dressing. Go to the local spray car wash; spray down the entire engine compartment with the tire cleaner, let sit for one minute, insert filthy lucre into the coin gobbler, and select rinse or soap, depending on how much filthy lucre you wish to feed the greedy machine. Use the high pressure water to remove the caked-on road slime and Kuwaiti dinosaur by-products. (It should go without saying, that you stay away from things like engine openings/seals, alternator, fuse/junction box, and distributor with the direct high-pressure stream, capisce?) Repeat these two steps as necessary, until the dirt and grease are gone. Allow to dry. Once this has taken place, spray down the engine compartment once again, this time with the protectant, until everything in sight is wet and shiny. This does not include your girlfriend, unless she's a body builder, although, come to think of it...
An-y-way...you're done. The excess protectant will dry or evaporate. Yes, it will attract a certain amount of dust, but if the dust becomes excessive, a simple rinse under the hood will get rid of the dust, and the protectant will keep your hoses, wiring bundles, and the engine room in general looking like showroom new, without going to a lot of time and trouble. If your girlfriend attracts a lot of dust, a gentle rubbing should remedy that...among other things.
Twisty roads and cheap fuel to all!