CONSTRUCTIVE criticism of how the piicture is posted and the technical merits thereof welcome.....
So, any guesses as to why I would be moved to put up this picture of an air hose as removed from the inlet manifold of a 280SE 3.5?
Stick, this photo is significantly better than your past quiz photo. Though I had no idea of what you were talking about in the quiz, the photo was good! (Oh, and don't be surprised if Dan Caron Dr. Benz "wins" all of your quiz offerings. He has paid his dues and seen it all...)
You
asked for "constructive criticism" so here it is.
1) Pay close attention to what you are trying to convey, and ensure the photo does that well.
2) Lighting, focus, sharpness and detail are all important.
You control
lighting by the use of added light, or reflectors. Reflectors need not be sophisticated; often a piece of white cardboard will do the trick. Usually the goal is to fill in the shadow areas.
Focus is from the camera--particularly with point and shoot, you need to allow time for the lens to adjust itself. Ensure you are within the bounds of the camera's capabilities--if the lens focus is from 1M to infinity, bringing it closer than 1 meter will give you out of focus shots. Yes, it's that simple.
Sharpness is most often a factor of holding the camera, combined with focus. Many cameras today have VR (vibration reduction) systems built into the lenses or the camera itself. While great, they don't replace a steady mount--like a tripod or even a monopod.
Detail is how much information is contained in the photo, and can be a factor of how you compose the shot, and the camera settings. If you shoot from far away, and have to crop out 90% of the photo, what remains will have less detail.
All that being said, how can anyone (not just you) improve photos of engine bays, or other detail?
1) Try to avoid a flash--casts too great a shadow. Most often you'll get the foreground "blown out" (overexposed) while the background/shadow are is underexposed.
2) Use lights--even a well-placed trouble light will be better than a flash. JA17 has lights mounted on stands in his shop--and no, he isn't a photographer. The lights allow a bright illumination to his
work area when he needs it. They are more like lights used by painters than photographers, and they'll do the trick.
3) Have a big sheet of white covered cardboard around to use as a reflector. You can often fill in shadow and better illuminate your "working area" by reflecting overhead shop light (or outdoor light) to better light your subject.
4) The more light the better, generally. Modern digital cameras, for all their good, don't do a great job in low light situations. Their built-in flash is often inadequate and really bad for close up work. Low light often causes the lens to be wide open, or the shutter speed to be very slow, and these together are a recipe for a bad photo--particularly if you are holding the camera! There will be photographic professionals that aim for wide-open lenses and long exposures--generally on a tripod for a specific look. They know how to manipulate light.
5) Most of us are not photographers--I get it. That doesn't mean you can't understand what you need and improvise. If you work on old cars, you must be a master of improvisation. Doesn't take much to make a light stand and nearly nothing to create a reflector. There are tripods and monopods out there that sell for $500 and more--and also ones that sell for $20.
Great photos of what YOU are trying to shoot are best taken in brightly lit areas with uniform light from all directions, rather than point-source light from a flash. This isn't much different than the kind of illumination you would like for working! Shooting outdoors? Do so on an overcast day. Specular light from noonday sun on a cloudless day makes for spectacularly challenging photos...
After looking at many thousands of photos, and editing a large number of them for the Pagoda book, I'll all over lighting quality. In a few cases in the book there were "snapshots" taken by the contributor, of a professional photo shoot in which their car was used as a prop. In the cases I remember of these shots, you'll see:
1) Stand mounted lights.
2) Reflectors
3) Gorgeous models.
You can get #1 and #2 easily yourself. For #3, contact Wolfmann!
You can use
free software like Picasa from Google to take your photos up in quality, too.
http://picasa.google.com/ 
