Only part of the scene renders I'm a newbie to Blender. First, thanks to all that help novices. I'm learning Blender Internal first.

My first project was to merge two existing shared blender files: first was an animation of 600 frames (20th Century Fox Intro). Then I imported shared 3D automobile objects. The merged scene (in 4 layers) looks fine in solid, material and even rendered VIEWS. But when I render the camera image (in BI or even in Cycles), the top half of the 3D scene is gray. Seems I have a solid gray plane (just above my grid plane) cutting off the image. But there is no plane object there. See my screen capture slice below.

I'm on a 2009 iMac with ATI Radeon HD Graphics (512MB), 3.06GHz Core 2 Duo CPU and 16GB of RAM.  Couldn't find a similar reported problem here or on the web.
QUESTION ANSWERED. I had checked for render borders, and camera clip distance and objects in Layer 1 blocking camera view and have determined it came in with the automobile in Layer 4. I couldn't see anything just above the grid floor. Then I noticed "Plane 022" in the Outliner with the Viewport (eyeball) disabled. Once I enabled it, I found it was a pan to help reflect light onto the automobile from the creator's original light sources. Only then could I see it. "X"! "Plane 022" gone and my BI render looks great now. Thanks for the help. Sorry about posting the sample image twice. Not used to this Blog.
Cheers.